Austria (quittio/country-at)

Not reviewed by a tax adviser yet. The legal wording, rules and defaults of this pack follow the law and the official sources as of October 2026, but have not been reviewed by an Austrian tax adviser. Check the mentions and rates of your invoices before you rely on them. Quittio is no tax or legal advice; the business that issues an invoice remains responsible for it.

The Austrian pack implements the mandatory invoice information of the Austrian VAT act (UStG 1994, Umsatzsteuergesetz), the Austrian national CIUS of EN 16931 (CIUS-AT-NAT, and CIUS-AT-GOV for the federal government), the Austrian XML invoice format ebInterface and the Austrian law on late payment. Its class is Quittio\Country\AT\CountryAT (code AT, translation namespace quittio-at).

• Legal references. This page writes Austrian legal references in English form: "section 11 (1) no. 3 lit. a UStG" stands for "§ 11 Abs. 1 Z 3 lit. a UStG", and "Art. 6 UStG" for an article of the annex to the UStG (the Binnenmarktregelung, the rules for the EU single market). Other laws cited are the Commercial Code (UGB, Unternehmensgesetzbuch), the Civil Code (ABGB, Allgemeines bürgerliches Gesetzbuch) and the Federal Fiscal Code (BAO, Bundesabgabenordnung). Values that the pack stores or prints in German keep their German form.
• Terms. The UID (Umsatzsteuer-Identifikationsnummer) is the Austrian VAT identifier, e.g. ATU12345678. A Gutschrift is a self-billed invoice, a Kleinunternehmer a small business that charges no VAT. e-Rechnung.gv.at is the portal of the federal government for incoming e-invoices, run by the Bundesrechenzentrum (BRZ) for the Federal Ministry of Finance (BMF).
• Not part of quittio/quittio. The pack is a package of its own, released with the same version as the rest of Quittio. If EN 16931, profile or CIUS are new to you, read E-invoicing basics first.

Installation#

composer require quittio/country-at

The pack needs PHP 8.3 and quittio/core of the same version. It is not part of quittio/quittio; install it next to quittio/quittio (Laravel) or next to quittio/core (without Laravel). It is developed in the monorepo Quittio/quittio and published as the read-only repository Quittio/country-at; please open issues and pull requests in the monorepo.

Laravel. The pack declares itself in its composer.json under extra.quittio.country-packs (Quittio\Country\AT\CountryAT), so Laravel registers it after composer require without further steps (Registering packs: Laravel). php artisan quittio:countries lists it. The pack has no service provider, no configuration file and no settings under quittio.countries.at. To invoice as an Austrian company, set your seller in config/quittio.php (Your company) with the country AT:

// config/quittio.php
'seller' => [
    'name' => 'Donau Werkstatt GmbH',
    'vat_id' => 'ATU12345678',                         // UID
    'address' => [
        'line1' => 'Mariahilfer Straße 1',
        'postcode' => '1060',
        'city' => 'Wien',
        'country' => 'AT',
    ],
    'bank_accounts' => [
        ['iban' => 'AT611904300234573201', 'bic' => 'BKAUATWW', 'name' => 'Donau Werkstatt GmbH'],
    ],
],

Quittio::invoice() then starts every invoice with this seller, and lines without vat: get the standard rate of 20 % (Default VAT).

Without Laravel. Pass the pack to Quittio::create() (Registering packs: without Laravel):

use Quittio\Core\Builder\InvoiceBuilder;
use Quittio\Core\Quittio;
use Quittio\Core\Tax\CountryDefaultVat;
use Quittio\Country\AT\CountryAT;

$quittio = Quittio::create(['country' => 'AT'], [new CountryAT]);
InvoiceBuilder::useDefaultVat(new CountryDefaultVat($quittio->countries()));   // lines without vat(): 20 %

Registering the pack adds it to the country registry, registers its profiles cius-at-nat and cius-at-gov, makes its ebInterface reader available to read() and validateFile(), and registers resources/lang as the translation namespace quittio-at. The option country is only the default for invoices whose seller has no country code.

When it applies#

The pack leads every invoice whose seller is in Austria (seller country code BT-40 AT), or whose run names it (->country('AT')). It then checks the UStG rules, chooses the format for Austrian public buyers (Format choice) and provides the defaults: German as language (unless the invoice or the configuration sets one), A4 paper, the free letter layout and the EPC GiroCode.

For an invoice from another country to a buyer in Austria, only the format rule of the pack applies: a buyer with an Austrian organisation number receives UBL after CIUS-AT-GOV, whatever the seller's country. The UStG rules are not applied to such invoices. Details are in How a pack is selected.

Without the pack, an Austrian seller gets the generic pack: EN 16931 rules only, and the warning QUITTIO-GENERIC-COUNTRY.

Common tasks#

Complete example#

An invoice of an Austrian company to an Austrian business, without Laravel. It is rendered as ZUGFeRD with the profile EN 16931 (the automatic format choice for a domestic business invoice), in German, and validated with the EN 16931 and UStG rules:

use Quittio\Core\Builder\InvoiceBuilder;
use Quittio\Core\Builder\Party;
use Quittio\Core\Enums\PaymentMeansCode;
use Quittio\Core\Enums\UnitCode;
use Quittio\Core\Quittio;
use Quittio\Core\Tax\CountryDefaultVat;
use Quittio\Country\AT\CountryAT;
use Quittio\Country\AT\Tax\VatPreset;

$quittio = Quittio::create(['country' => 'AT'], [new CountryAT]);
InvoiceBuilder::useDefaultVat(new CountryDefaultVat($quittio->countries()));   // lines without vat(): 20 %

$invoice = InvoiceBuilder::make()
    ->number('RE-2026-0042')
    ->issueDate('2026-10-05')
    ->deliveryDate('2026-09-30')                                      // date of the supply (AT-USTG-04)
    ->seller(Party::make('Donau Werkstatt GmbH')
        ->vatId('ATU12345678')                                        // UID of the seller (AT-USTG-03)
        ->address('Mariahilfer Straße 1', '1060', 'Wien', 'AT')
        ->contact('Anna Huber', '+43 1 234567', '[email protected]'))
    ->buyer(Party::make('Tiroler Handel KG')
        ->vatId('ATU87654321')                                        // required above 10,000 EUR gross (AT-USTG-05)
        ->address('Maria-Theresien-Straße 10', '6020', 'Innsbruck', 'AT'))
    ->line('Softwareentwicklung', netPrice: '100.00', quantity: 12, unit: UnitCode::Hour)   // 20 %
    ->line('Fachbuch', netPrice: '45.00', vat: VatPreset::Reduced)                          // 10 %
    ->paymentTerms(fn ($terms) => $terms->dueInDays(14))
    ->payment(PaymentMeansCode::SepaCreditTransfer, iban: 'AT611904300234573201', bic: 'BKAUATWW')
    ->build();

$result = $quittio->make($invoice)->render();

$result->format();                          // "zugferd"
$result->profile()?->key();                 // "en16931"
$result->validation()->isValid();           // true: no errors (and here no warnings either)
$result->data()->totals?->grossTotal;       // EUR 1489.50
$result->save(__DIR__.'/invoices/');        // invoices/Rechnung_RE-2026-0042.pdf

render() throws a ValidationException when a rule reports an error, e.g. AT-USTG-04 without a delivery date (Validation). The PDF carries a GiroCode for the transfer (Payment QR code). In Laravel, start with Quittio::invoice() instead of InvoiceBuilder::make()->seller(…); the rest of the chain is the same.

Tax presets#

A tax preset is a ready-made VAT treatment for an invoice line. It sets the VAT category (BT-151) and the rate, and for exempt supplies also the exemption reason code (BT-121) and text (BT-120). Use a preset instead of a bare category and rate: the line then carries the wording the UStG requires, and the Austrian rules recognise the case. Lines without vat: take the default VAT: VatPreset::Standard for an Austrian seller, VatPreset::SmallBusiness for a small business.

The categories are the codes of EN 16931: S standard rate, E exempt, AE reverse charge, K intra-community supply, G export outside the EU, O not subject to VAT (see Categories).

Quittio\Country\AT\Tax\VatPreset is a string-backed enum that implements DatedTaxPreset. Apply it per line:

use Quittio\Core\Builder\InvoiceBuilder;
use Quittio\Core\Enums\UnitCode;
use Quittio\Country\AT\Tax\VatPreset;

$builder = InvoiceBuilder::make()
    // ... number, dates, seller and buyer as in the complete example
    ->line('Softwareentwicklung', netPrice: '100.00', quantity: 12, unit: UnitCode::Hour, vat: VatPreset::Standard)   // 20 %
    ->line('Fachbuch', netPrice: '45.00', vat: VatPreset::Reduced)                                                     // 10 %
    ->line('Milch', netPrice: '1.50', quantity: 10, unit: UnitCode::Litre, vat: VatPreset::BasicFood)                 // 4.9 % for a supply from 1 July 2026
    // an exemption without its own case: the legal reference;
    // the invoice prints "Steuerfrei gemäß § 6 Abs. 1 Z 19 UStG"
    ->line('Ärztliche Leistung', netPrice: '300.00', vat: VatPreset::exempt('§ 6 Abs. 1 Z 19 UStG'));

The codes in column BT-121 are VATEX codes: the standard codes for the reason of an exemption. SmallBusiness has none.

BasicFood takes the rate that applied on the supply date of the line (TaxTables::BASIC_FOOD_RATE): a delivery on 30 June 2026 gets 10 %, one on 1 July 2026 gets 4.9 %. The supply date is found as for the German presets (Germany: tax presets): the end of the line period, its start, the VAT point date, the delivery date, the end of the invoicing period or the issue date. VatPreset::BasicFood->rate() returns the rate of today in Vienna. The other rates are fixed (TaxTables::STANDARD_RATE, REDUCED_RATE, REDUCED_RATE_13).

Exemption texts#

Standard, Reduced, Reduced13 and BasicFood carry no text, because EN 16931 forbids an exemption reason for taxed supplies (BR-S-10). The other presets print an exemption reason (BT-120) in German or English, from resources/lang/{de,en}/tax.php:

How presets behave#

• Language. The text is taken in the invoice locale (->locale() on the builder) when the line is built. Without a locale it is German. The enum cases take German for regional locales such as de_AT and English for locales the pack does not ship (e.g. fr). VatPreset::exempt() (a Quittio\Country\AT\Tax\CustomVatPreset) behaves the same: German without a locale and for de_AT.
• Preset key. The key stays on the line ($line->vat->presetKey). The small business detection (AT-USTG-08) and the deadline of AT-USTG-12 rely on it.
• VAT breakdown. Category, rate, code and text flow into the VAT breakdown (BG-23). The PDF lists the exemption texts in its legal notes.
• No invoice notes. Unlike some German presets, the Austrian presets add no invoice note (BT-22); the exemption text is in BT-120 only.
• Allowances and charges. Document level allowances and charges take a category and a rate, not a preset: ->charge(VatCategory::StandardRate, '20', amount: '10.00', reason: 'Versand').
• Lookup by key, e.g. from a database column: VatPreset::from('at.standard'), VatPreset::fromKey($key) (null for keys of other packs), (new CountryAT)->taxPresets()->get('at.standard') or, across all installed packs, $quittio->countries()->taxPreset('at.standard'). at.exempt is not part of the collection. In Laravel, quittio.defaults.vat takes a key, e.g. 'at.reduced' (Defaults).

Small businesses#

A small business (Kleinunternehmer) applies the exemption of section 6 (1) no. 27 UStG and must not show VAT on its invoices (section 11 (12) UStG). Three steps make an invoice a small business invoice in Quittio:

1. Mark the seller as a small business. Set quittio.seller.small_business = true in Laravel (Small businesses), or ->flag(Meta::FLAG_SMALL_BUSINESS) on the builder.
2. Use VatPreset::SmallBusiness on every line. Lines without vat: get it automatically when the invoice has the flag and the default VAT comes from the country pack (CountryDefaultVat; in Laravel always). A line with this preset also marks the invoice as small business invoice, without the flag.
3. Identify the seller without a UID. EN 16931 requires the seller's VAT identifier or tax number (BT-32) for category E (BR-E-02), and a VAT identifier, seller identifier (BT-29) or legal registration (BT-30) so that the buyer can identify the seller (BR-CO-26).

use Quittio\Core\Builder\InvoiceBuilder;
use Quittio\Core\Builder\Party;
use Quittio\Core\Data\Meta;
use Quittio\Core\Enums\PaymentMeansCode;
use Quittio\Core\Quittio;
use Quittio\Core\Tax\CountryDefaultVat;
use Quittio\Country\AT\CountryAT;

$quittio = Quittio::create([], [new CountryAT]);
InvoiceBuilder::useDefaultVat(new CountryDefaultVat($quittio->countries()));

$invoice = InvoiceBuilder::make()
    ->number('RE-2026-0007')
    ->issueDate('2026-10-05')
    ->deliveryDate('2026-10-01')
    ->flag(Meta::FLAG_SMALL_BUSINESS)
    ->seller(Party::make('Grafikstudio Maria Berger')
        ->taxNumber('12 345/6789')                  // BT-32 (BR-E-02)
        ->identifier('L-4711')                      // BT-29, e.g. your supplier number at the buyer (BR-CO-26)
        ->address('Hauptplatz 3', '8010', 'Graz', 'AT'))
    ->buyer(Party::make('Steirische Bäckerei OG')->address('Herrengasse 5', '8010', 'Graz', 'AT'))
    ->line('Logo-Entwurf', netPrice: '650.00')       // VatPreset::SmallBusiness through the default VAT
    ->paymentTerms(fn ($terms) => $terms->dueInDays(14))
    ->payment(PaymentMeansCode::SepaCreditTransfer, iban: 'AT611904300234573201')
    ->build();

$result = $quittio->make($invoice)->render();       // "Umsatzsteuerfrei aufgrund der Kleinunternehmerregelung (§ 6 Abs. 1 Z 27 UStG)."

A small business invoice is a simplified invoice: it needs neither the buyer's address nor the UIDs. VAT on it is an error (AT-USTG-08).

Reverse charge and intra-community supplies#

• Services to a business in another member state. Use VatPreset::ReverseChargeEu. The text names the transfer of the tax liability ("Übergang der Steuerschuld auf den Leistungsempfänger"), which AT-USTG-06 requires. Issue the invoice by the 15th of the month after the service (AT-USTG-12).
• Domestic reverse charge. Use VatPreset::ReverseChargeDomestic (section 19 (1a) to (1e) UStG).
• Intra-community supply of goods. Use VatPreset::IntraCommunitySupply. EN 16931 also needs the country of the delivery address (BR-IC-12): ->deliverTo('Isar Consulting GmbH', Address::make('Leopoldstraße 20', '80802', 'München', 'DE')).
• VAT identifiers. Reverse charge and intra-community supplies are never simplified invoices: the UIDs of seller and buyer are checked (AT-USTG-03, AT-USTG-05), and the mandatory PDF output requires the buyer's VAT identifier.

use Quittio\Core\Builder\InvoiceBuilder;
use Quittio\Core\Builder\Party;
use Quittio\Core\Enums\UnitCode;
use Quittio\Country\AT\Tax\VatPreset;

$builder = InvoiceBuilder::make()
    // ... number, dates and payment as in the complete example
    ->seller(Party::make('Donau Werkstatt GmbH')->vatId('ATU12345678')->address('Mariahilfer Straße 1', '1060', 'Wien', 'AT'))
    ->buyer(Party::make('Isar Consulting GmbH')->vatId('DE987654321')->address('Leopoldstraße 20', '80802', 'München', 'DE'))
    ->line('Beratung', netPrice: '120.00', quantity: 10, unit: UnitCode::Hour, vat: VatPreset::ReverseChargeEu);

Without a preset, AT-USTG-06 accepts a BT-120 text of category AE that contains "Steuerschuld", "reverse charge", "reverse-charge", "autoliquidation", "inversione contabile" or the text of one of the reverse charge presets in any locale (case-insensitive).

Simplified invoices#

UstgRules::isSimplifiedInvoice($invoice) decides whether the simplifications of section 11 (6) UStG apply. An invoice is simplified when it

• is in euro and its gross total (BT-112) is at most 400 EUR (150 EUR for invoices issued before 1 March 2014, TaxTables::SIMPLIFIED_INVOICE_LIMIT), or
• is a small business invoice (Small businesses).

Invoices with reverse charge (category AE) or an intra-community supply (K) are never simplified. A simplified invoice needs neither the buyer's name and address (AT-USTG-02) nor the UID of the seller (AT-USTG-03) or the buyer (AT-USTG-05), and AT-USTG-10 does not apply. There is no builder macro: the rules recognise the case from the amounts and presets.

UStG rules#

UstgRules::all() checks the mandatory information of section 11 UStG on every invoice whose leading pack is the Austrian one, in every format. The rules run at validation level L3 (Validation levels). Switch single rules off or change their severity with validation.rules (Switching rules off).

Late invoices stay valid, so AT-USTG-11 and AT-USTG-12 are warnings. Messages and hints exist in German and English (Translations). The rules also offer helpers for your own code: UstgRules::isSimplifiedInvoice(), isSmallBusinessInvoice(), needsBuyerVatId(), hasServiceDate() and supplyDate().

Profiles#

The pack registers two profiles of the Austrian CIUS of EN 16931, as published by the BRZ for the BMF (CIUS-AT-NAT, CIUS-AT-GOV). Both have the level EN 16931 and the syntaxes CII and UBL. Embedded in a ZUGFeRD PDF, they have the conformance level "EN 16931" with their own specification identifier (Profiles).

cius-at-gov is chosen automatically for public buyers (Format choice). cius-at-nat is used only when you request it, in any format with CII or UBL:

$result = $quittio->make($invoice)->profile('cius-at-nat')->render();               // ZUGFeRD with CIUS-AT-NAT
$result = $quittio->make($invoice)->format('ubl')->profile('cius-at-nat')->render();

The reader recognises both profiles by their specification identifier once the pack is registered (Reading incoming invoices).

The CIUS documents state no severity; every rule is an error at level L3. Where EN 16931 forbids a value that the CIUS makes mandatory (the VAT rate of category O, BR-O-05 to BR-O-07), EN 16931 wins.

CIUS-AT-NAT (CiusAtRules::national()):

CIUS-AT-GOV adds the rules of e-Rechnung.gv.at (CiusAtRules::government()):

Format choice#

Formats\AustrianFormatRule is the format rule of the pack. A buyer whose electronic address (BT-49) has the scheme 9915 (Austrian organisation number, e.g. b for the federal government) receives UBL after cius-at-gov. This applies to domestic invoices and, as buyer pack, to invoices from other countries.

Everything else follows the automatic format choice of the core: a domestic invoice to a business becomes ZUGFeRD with the configured profile (default en16931), an invoice to a consumer a PDF. Austria has no e-invoicing obligation between businesses, so the pack prescribes nothing else. prepare() shows the choice without rendering, and ->format() overrides it.

Invoices to the federal government#

use Quittio\Core\Builder\InvoiceBuilder;
use Quittio\Core\Builder\Party;
use Quittio\Core\Enums\PaymentMeansCode;
use Quittio\Core\Enums\UnitCode;
use Quittio\Core\Quittio;
use Quittio\Core\Tax\CountryDefaultVat;
use Quittio\Country\AT\CountryAT;

$quittio = Quittio::create([], [new CountryAT]);
InvoiceBuilder::useDefaultVat(new CountryDefaultVat($quittio->countries()));

$invoice = InvoiceBuilder::make()
    ->number('RE-2026-0046')
    ->issueDate('2026-10-05')
    ->deliveryDate('2026-09-30')
    ->buyerReference('4700000001')                 // order reference (Auftragsreferenz) of the ordering office (AT-GOV-01)
    ->seller(Party::make('Donau Werkstatt GmbH')
        ->vatId('ATU12345678')
        ->address('Mariahilfer Straße 1', '1060', 'Wien', 'AT')
        ->contact('Anna Huber', '+43 1 234567', '[email protected]'))   // AT-GOV-02
    ->buyer(Party::make('Bundesministerium für Beispiele')
        ->address('Musterplatz 1', '1010', 'Wien', 'AT')
        ->electronicAddress('b', '9915'))          // scheme 9915: UBL after CIUS-AT-GOV
    ->line('Softwareentwicklung', netPrice: '100.00', quantity: 12, unit: UnitCode::Hour)
    ->paymentTerms(fn ($terms) => $terms->dueInDays(30))
    ->payment(PaymentMeansCode::SepaCreditTransfer, iban: 'AT611904300234573201', bic: 'BKAUATWW')   // code 58 (AT-GOV-03)
    ->build();

$result = $quittio->make($invoice)->render();
$result->format();             // "ubl"
$result->profile()?->key();    // "cius-at-gov"
$result->xml();                // the UBL to upload to e-Rechnung.gv.at

If you have a ten digit order number, set it as purchase order reference (BT-13) and give every line its order line reference: ->line(fn ($line) => $line->name('…')->…->orderLineReference('10')) (AT-GOV-09).

ebInterface#

ebInterface 6.1 is the Austrian XML invoice format of AUSTRIAPRO; e-Rechnung.gv.at accepts it besides UBL. The pack writes and reads it.

use Quittio\Core\Builder\InvoiceBuilder;
use Quittio\Core\Builder\Party;
use Quittio\Core\Calculation\En16931Calculator;
use Quittio\Core\Enums\PaymentMeansCode;
use Quittio\Core\Enums\UnitCode;
use Quittio\Core\Quittio;
use Quittio\Country\AT\CountryAT;
use Quittio\Country\AT\EbInterface\EbInterfaceWriter;
use Quittio\Country\AT\Tax\VatPreset;

$quittio = Quittio::create([], [new CountryAT]);

$invoice = InvoiceBuilder::make()
    ->number('RE-2026-0046')
    ->issueDate('2026-10-05')
    ->deliveryDate('2026-09-30')
    ->purchaseOrderReference('4700000001')        // OrderID of the invoice recipient
    ->seller(Party::make('Donau Werkstatt GmbH')->vatId('ATU12345678')->address('Mariahilfer Straße 1', '1060', 'Wien', 'AT'))
    ->buyer(Party::make('Tiroler Handel KG')->vatId('ATU87654321')->address('Maria-Theresien-Straße 10', '6020', 'Innsbruck', 'AT'))
    ->line(fn ($line) => $line->name('Softwareentwicklung')->quantity(12, UnitCode::Hour)->netPrice('100.00')->vat(VatPreset::Standard)->orderLineReference('10'))
    ->paymentTerms(fn ($terms) => $terms->dueInDays(14))
    ->payment(PaymentMeansCode::SepaCreditTransfer, iban: 'AT611904300234573201', bic: 'BKAUATWW')
    ->build();

$xml = (new EbInterfaceWriter)->write((new En16931Calculator)->calculate($invoice));
file_put_contents('RE-2026-0046.xml', $xml);

$read = $quittio->read($xml);   // the reader of the pack
$read->syntax;                  // "ebinterface"
$read->profile;                 // null
$read->data->number;            // "RE-2026-0046"

Writer (EbInterface\EbInterfaceWriter):

• write(InvoiceData $invoice): string takes a calculated invoice (with totals); an invoice without totals throws an InvalidArgumentException. Calculate it with En16931Calculator, or take $result->data() of a render run.
• It follows the official mapping of AUSTRIAPRO between UBL and ebInterface. The purchase order reference (BT-13), else the buyer reference (BT-10), is the order reference of the invoice recipient (OrderID, the Auftragsreferenz of the federal government) and of every line with its order line reference (BT-132, OrderPositionNumber). The first seller identifier (BT-29) is the supplier number (InvoiceRecipientsBillerID).
• A missing VAT identifier of seller or buyer is written as ATU00000000 (EbInterfaceWriter::UNDEFINED_VAT_ID).
• The type code sets the document type (EbInterfaceWriter::documentType()): credit notes (381, 261) are a CreditMemo with positive amounts, prepayment invoices (386) InvoiceForAdvancePayment, partial invoices (326) InvoiceForPartialDelivery, self-billed invoices (389) SelfBilling, final payment requests (218) FinalSettlement, debit notes (383) SubsequentDebit, everything else Invoice.
• The root element carries GeneratingSystem="Quittio", the currency, the title of the presentation as DocumentTitle and the two-letter language of the invoice locale.
• Fields without a place in ebInterface are not written, e.g. the payee (BG-10), the buyer reference next to a purchase order reference, attachments and the VAT in accounting currency (BT-111).

Reader (EbInterface\EbInterfaceReader):

• It reads ebInterface 6.0 and 6.1 (EbInterfaceReader::NAMESPACES). CountryAT::readers() registers it, so read(), readFile(), validateFile() and validatePath() accept such files once the pack is registered (Reading incoming invoices).
• The mapping is that of the writer in reverse. The result has the syntax ebinterface and no profile; the rules use the configured default profile.
• The language attribute sets the locale of the data, and the declared amounts are compared with a recalculation as for other formats.
• The XSD level (L4) of the core has schemas for CII and UBL only and skips ebInterface files; the reader checks their structure, the other levels their content (Incoming files).

ebInterface is not an output format of render() yet; the XML formats of the core are CII and UBL (CII and UBL). Use the writer directly. The pack's tests check its output against the schema of ebInterface 6.1.

Self-billing (Gutschrift)#

A self-billed invoice is issued by the buyer in the name of the seller. Set its type code (->type(InvoiceTypeCode::SelfBilledInvoice), 389; see Credit notes, corrected invoices and self-billing) and label it "Gutschrift" (section 11 (8) no. 3 UStG). The pack has no builder macro for it; add the note yourself:

use Quittio\Core\Enums\InvoiceTypeCode;
use Quittio\Core\Enums\NoteSubjectCode;
use Quittio\Country\AT\Texts\LegalTexts;

$builder->type(InvoiceTypeCode::SelfBilledInvoice)
    ->note(LegalTexts::text(LegalTexts::SELF_BILLING), NoteSubjectCode::RegulatoryInformation);   // "Gutschrift"

Without the note, AT-USTG-09 is an error for a PDF without XML and a warning for an e-invoice. The PDF and HTML title of a self-billed invoice is "Gutschrift" (English "Self-billed invoice (Gutschrift)") from the correction policy, and the mandatory PDF output requires it to be printed. ebInterface writes such an invoice as SelfBilling.

Cancellations and corrections#

CountryAT::correctionPolicy() sets how invoices of an Austrian seller are cancelled and corrected (see Building invoices: cancellations and corrections and CorrectionPolicy):

• Cancellation strategy credit_note: a cancellation is a credit note (type code 381) with positive amounts.
• Correction strategy cancel_and_reissue: the Managed layer corrects an invoice by cancelling it and issuing a new one.

Change them with quittio.corrections.cancellation_strategy and quittio-managed.correction.strategy. The policy sets these titles:

A price reduction (Quittio::priceReduction()) has no Austrian title and takes the label of the core. Locales other than German and English take the English title.

$cancellation = $quittio->cancellation($result->data(), 'ST-2026-0001', reason: 'Doppelt verrechnet');
$quittio->make($cancellation)->render()->filename();   // "Stornorechnung_ST-2026-0001.pdf"

Late payment#

When a customer pays late, the Austrian Commercial Code (UGB) gives a business creditor default interest from a business debtor and a flat rate for recovery costs; a consumer owes the statutory interest of the Civil Code (ABGB). The pack provides these values and a calculator. Quittio's documents do not apply them by themselves: calculate the interest with DefaultInterest and pass the results to a payment reminder (Documents: payment reminders).

CountryAT::dunningLaw() (also CountryAT::austrianDunningLaw() without an instance) returns these values (DunningLaw):

Default interest#

Quittio\Country\AT\Dunning\DefaultInterest calculates the default interest on an open amount:

use Brick\Money\Money;
use Quittio\Core\Builder\Party;
use Quittio\Core\Documents\DocumentBuilder;
use Quittio\Core\Quittio;
use Quittio\Core\Support\Date;
use Quittio\Country\AT\CountryAT;
use Quittio\Country\AT\Dunning\DefaultInterest;

$quittio = Quittio::create([], [new CountryAT]);
$interest = new DefaultInterest;

$reminder = DocumentBuilder::paymentReminder(1)                     // first reminder ("1. Mahnung")
    ->number('M-2026-0003')
    ->issueDate('2026-10-05')
    ->seller(Party::make('Donau Werkstatt GmbH')->vatId('ATU12345678')->address('Mariahilfer Straße 1', '1060', 'Wien', 'AT'))
    ->buyer(Party::make('Tiroler Handel KG')->vatId('ATU87654321')->address('Maria-Theresien-Straße 10', '6020', 'Innsbruck', 'AT'))
    ->creditTransfer('AT611904300234573201', 'BKAUATWW')
    ->openItem('RE-2026-0042', '2026-06-01', '1440.00', dueDate: '2026-06-15')
    // first day with interest: the day after the due date; 2026-10-05 is the first day without interest
    ->interestCharge(...$interest->calculate(Money::of('1440.00', 'EUR'), Date::parse('2026-06-16'), Date::parse('2026-10-05')))
    ->flatRate('RE-2026-0042')                                         // 40.00 EUR, once per claim, only from businesses
    ->deadline('2026-10-19')
    ->build();

$reminder->dunning->total('EUR');                                      // EUR 1526.99: 1,440.00 + 46.99 interest + 40.00
$quittio->document($reminder)->render()->save(__DIR__.'/reminders/');

• Descriptions. With a German locale (the default, also de_AT) a description reads "Verzugszinsen 10,73 % p. a. (Basiszinssatz 1,53 % + 9,20 Prozentpunkte, § 456 UGB) vom 16.06.2026 bis 04.10.2026", for a consumer "Verzugszinsen 4,00 % p. a. (§ 1000 Abs. 1 ABGB) vom 16.06.2026 bis 04.10.2026". With locale: 'en' they are English: "Default interest 10.73 % p. a. (base rate 1.53 % + 9.20 percentage points, section 456 UGB) from 2026-06-16 to 2026-10-04". Other locales take German. The texts are LegalTexts::DEFAULT_INTEREST and DEFAULT_INTEREST_CONSUMER (Legal texts).
• Day count. The charges count 365 days per year (InterestCharge::$dayCount); interestCharge() takes it over.
• Periods. A charge covers a whole period with the same base rate. A table entry that keeps the rate (e.g. 1 July 2026) starts no new period.
• Flat rate. DocumentBuilder::flatRate($claim) adds 40.00 EUR as fee of kind DunningFeeKind::FlatRate for one claim. The builder rejects a second flat rate for the same claim in one reminder and a flat rate for a consumer; a flat rate together with reminder fees gets the notice QUITTIO-DUNNING-FLAT-RATE-FEES (Documents: payment reminders). Which claims already carried it in earlier reminders is up to your application or the Managed layer.
• Core calculator. Quittio\Core\Dunning\DefaultInterest::forCountry(new CountryAT) calculates the same rates from referenceRates() and dunningLaw(), with the descriptions of the core instead of the Austrian texts.

Base rate table#

Quittio\Country\AT\Dunning\BaseRateTable holds the base rate (Basiszinssatz) of the OeNB for contracts concluded from 16 March 2013. The rate on the first day of a half-year applies to the whole half-year. CountryAT::referenceRates() returns the table. Quittio ships these rates (BaseRateTable::PUBLISHED):

Rates after the last entry are unknown until they are published. Interest for days from 1 January 2027 is therefore rejected instead of silently using the old rate. The pack has no configuration or automatic update for new rates: add a published rate to a table and pass it to DefaultInterest (the value below is an example, not the published rate):

use Quittio\Country\AT\Dunning\BaseRateTable;
use Quittio\Country\AT\Dunning\DefaultInterest;

$rates = (new BaseRateTable)->withRate('2027-01-01', '1.78');
$interest = new DefaultInterest($rates);

Payment QR code#

The pack's default payment QR code is girocode, and it brings no generator of its own. With the default paymentQr setting auto, the PDF therefore prints the EPC GiroCode of the core next to the bank details: for invoices in euro with a SEPA credit transfer (payment means 30 or 58) and a valid IBAN. Conditions, payload and options are described in Templates: payment QR codes; none switches the code off.

Mandatory PDF output#

After rendering, the mandatory field guard checks that the PDF shows certain values (Templates: mandatory field guard). CountryAT::mandatoryOutput() adds these Austrian values to the base fields. Paths without a value are skipped. The legal basis is the value Quittio reports, in German citation form.

The default templates print all of them.

Legal texts#

Quittio\Country\AT\Texts\LegalTexts::catalog() (also CountryAT::legalTexts()) holds the Austrian notices in German and English. Its fallback locale is German (LegalTexts::FALLBACK_LOCALE).

• REVERSE_CHARGE, INTRA_COMMUNITY_SUPPLY, EXPORT and SMALL_BUSINESS are the exemption reasons of the named tax presets, in every locale the pack ships, so a notice has one wording in BT-120 and in your notes. The other three come from resources/lang/{de,en}/legal.php.
• All texts are read through the translator, so overrides of tax.php and legal.php change them (Translations).
• LegalTexts::text($key, $locale, $replace) returns a text in $locale, else in its language (de_AT → German, en_GB → English), else in German. LegalTexts::localeOf($key, $locale) names the catalog locale it uses.
• Validation and rendering add no text.

Meta flags and settings#

The pack defines no meta flags of its own. It reads the small business flag of the core, Meta::FLAG_SMALL_BUSINESS (small_business), set by quittio.seller.small_business, a Managed issuer or ->flag() (Small businesses).

The pack has no settings: there is no quittio.countries.at section and no configuration file to publish (Settings of a pack). It has no builder macros either.

Defaults#

For pack authors and for reference, this is how CountryAT fills the CountryPack contract:

• Locale. German (de), unless the run, the invoice or the configuration sets another (Translations and locales). Dates are printed as dd.MM.yyyy.
• Paper and letter layout. A4 (Paper size) and the free layout without a norm (Letter layouts). The pack has no Austrian letter layout.
• Numbering. RE-{Y}-{seq:4}, e.g. RE-2026-0042, reset every year: a consecutive number with one or more series that identifies the invoice once (section 11 (1) no. 3 lit. h UStG). The Managed layer uses it when neither the issuer nor the configuration sets a pattern (NumberingRules).
• Retention. new RetentionRule(7, fromEndOfCalendarYear: true): invoices are kept for seven years from the end of the calendar year (section 11 (2) UStG, section 132 BAO). An invoice issued on 5 October 2026 is kept until 31 December 2033. Longer periods for property related supplies (section 18 (10) UStG) are not modelled (RetentionRule).
• Correction policy. See Cancellations and corrections.

Translations#

The pack ships German and English catalogs in resources/lang/{de,en}/ (CountryAT::locales() returns ['de', 'en']):

• rules.php: message and hint of every rule (AT-USTG-*, AT-NAT-*, AT-GOV-*);
• tax.php: the exemption reason texts of the presets, including at.exempt for VatPreset::exempt() (placeholder :paragraph);
• legal.php: the label "Gutschrift" and the default interest descriptions.

They are registered as the namespace quittio-at (e.g. quittio-at::rules.AT-USTG-03.message). CountryAT::registerTranslations() registers them lazily, so presets work without a Quittio instance. Rule messages and preset texts in other locales fall back to English, legal texts to German. Validation messages are written in the language set by validation.locale (Messages and translations).

Laravel. Laravel's translator is used, so the usual override files apply: lang/vendor/quittio-at/{locale}/rules.php, tax.php and legal.php, also for additional locales (Laravel: translations). A file only needs the keys you change:

// lang/vendor/quittio-at/de/tax.php
return [
    'at.reverse_charge_eu' => 'Reverse Charge – Übergang der Steuerschuld auf den Leistungsempfänger',
];

Without Laravel. Register a directory with {locale}/{group}.php files under the namespace of the pack after creating the Quittio instance; later paths override earlier ones:

use Quittio\Core\I18n\Translations;
use Quittio\Core\Quittio;
use Quittio\Country\AT\CountryAT;

$quittio = Quittio::create([], [new CountryAT]);
Translations::translator()->addPath(__DIR__.'/lang', CountryAT::TRANSLATION_NAMESPACE);   // e.g. lang/de/tax.php

A changed reverse charge text still satisfies AT-USTG-06, because the rule accepts the current texts of the reverse charge presets. Texts defined in PHP cannot be translated through files: the correction policy titles (German and English, fallback English) and the number and date format of the default interest descriptions (German for German locales, otherwise ISO dates).

Known limitations#

• The legal wording, references and defaults follow the law and official sources of October 2026 and have not been reviewed by an Austrian tax adviser. Later changes of the law need a new release.
• ebInterface is not a format of render(); use EbInterfaceWriter. validateFile() does not check ebInterface files against their schema (ebInterface).
• There is no Austrian letter layout (ÖNORM A 1080 was withdrawn without a successor), no Laravel service provider and no settings.
• The shipped base rate table ends with 1 July 2026. Later rates must be added with withRate(); there is no configuration key and no automatic update (Base rate table).
• There are no builder macros for Austrian special cases: the "Gutschrift" note, prepayment invoices and the conversion of foreign currency amounts are set with the general builder methods.
• AT-USTG-10 cannot read a conversion method stated in a note and only warns.
• Longer retention periods for property related supplies (section 18 (10) UStG) are not modelled.
• The documents layer checks the flat rate of section 458 UGB within one reminder only (once per claim, not for consumers); across reminders the application or the Managed layer must track it. When a consumer is in default is not modelled.
• The pack defines no buyer country rules and no exporters.