How to issue an invoice in Bulgaria: requisites and deadlines

When you actually need to issue an invoice

An invoice (фактура) is the official accounting document proving you sold something and at what price. If your company is VAT-registered (VAT, value-added tax, the tax you charge on sales), the rule is strict: you issue an invoice for every taxable supply, whether or not the client asked for one (Art. 113(1) of Bulgaria's VAT Act, ЗДДС).

If your company isn't VAT-registered, say you're a freelancer under the mandatory registration threshold, you still issue an invoice, just without a VAT line: the law explicitly bars unregistered persons from showing tax on their invoices (Art. 113(9) of the VAT Act). This is sometimes called a "simplified" invoice: it's the same document, minus the tax lines, because there's nothing to charge.

There's one exception, for sales to individuals (private customers, not companies): you only issue an invoice if the customer asks for one, otherwise a fiscal cash receipt is enough (Art. 113(3) of the VAT Act). If the customer does ask, you must issue it, even for a simple cash sale.

This guide covers ordinary domestic invoicing, to clients in Bulgaria. If you bill business clients elsewhere in the EU, different rules apply, reverse charge and VIES filings, covered separately in the link at the end of this article.

What a Bulgarian invoice must contain: Art. 114 of the VAT Act

The law spells out exactly what an invoice must contain, and there's no room to improvise. A missing requisite isn't a minor formality: it can mean your client cannot deduct the VAT on that invoice, even if everything else about it is fine.

• The document's name: "Фактура" (Invoice).
• A sequential, ten-digit number using Arabic numerals only, no spaces, no gaps, no repeats, based on one or more numbering series.
• The date of issue.
• The name and address of the supplier (your company) and of the recipient (the client).
• The ЕИК (Bulgaria's Unified Identification Code, essentially the company registration number) or БУЛСТАТ of the supplier and of the recipient, if the recipient is a company.
• The VAT number of the supplier and of the recipient, if both are VAT-registered.
• The quantity and description of the goods or service.
• The date the taxable event occurred (see the next section), if different from the date of issue.
• The unit price excluding VAT, and any commercial discounts not already reflected in the price.
• The tax base: the amount VAT is calculated on.
• The VAT rate, and the legal grounds if you're applying a zero rate or an exemption.
• The amount of VAT due.
• The total amount payable, if different from the tax base plus VAT.

One small but important detail: the invoice number can't skip, repeat, or restart mid-series. Whatever system you invoice through needs to keep that sequence intact on its own. This is exactly why manually tracked numbers in a spreadsheet are such a common source of errors when NAP, Bulgaria's National Revenue Agency, checks your records.

The deadline: 5 days from the taxable event

An invoice isn't issued "whenever it's convenient," there's a firm deadline. It must go out no later than 5 days from the date the taxable event occurred, or from the date you received an advance payment, if that payment came before the actual delivery (Art. 113(4) of the VAT Act).

The taxable event, in the ordinary case, is the moment the goods were actually handed over or the service was actually completed, not the date on the contract and not the date the client paid, unless payment came before delivery, in which case the payment date is what counts.

Why the deadline matters beyond the invoice itself: invoices issued and received during the month feed into the purchase and sales ledgers you file alongside the monthly VAT return, by the 14th of the following month. An invoice issued late, or dated into the wrong period, can throw off that entire month's filing and trigger a fine, on top of any problem it creates for your client's own VAT deduction.

Made a mistake? Credit and debit notes

Once issued, an invoice is never deleted or edited, not even for a plain typo in the amount. If the tax base of a supply changes after you've already issued the invoice, say the client returns part of the goods, you agree to a discount afterward, or the deal falls through entirely, the law provides a separate document for it: a notice to the invoice (Art. 115 of the VAT Act).

• Credit note (кредитно известие): issued when the tax base decreases or the supply is cancelled entirely (returned goods, a cancelled service, a discount agreed after the invoice).
• Debit note (дебитно известие): issued when the tax base increases (extra work, an additional charge on top of an already-invoiced supply).

The notice carries all the same requisites as a regular invoice, plus an explicit reference to the number and date of the invoice it corrects. It must be issued within the same 5-day window, but counted from the date of whatever triggered it: the return, the agreed discount, or the moment the error was spotted.

Practical tip: if you simply entered the wrong amount, the cleanest fix is a credit note that cancels the incorrect invoice entirely, followed by a fresh, correct one, not an attempt to "edit" the original in place.

Invoicing in EUR from 2026

As of 1 January 2026, Bulgaria is part of the eurozone, and that directly changes what your invoice looks like. From that date, every new invoice is issued in euro only, regardless of the currency the underlying deal was agreed in (the Law on the Introduction of the Euro in the Republic of Bulgaria, ЗВЕРБ).

• Invoices issued before 1 January 2026 stay valid in lev, they aren't reissued just because of the currency changeover.
• Conversions between lev and euro use the fixed rate of 1 EUR = 1.95583 BGN, the same peg the lev has held to the euro since 1999.
• Dual BGN/EUR display remains mandatory on price tags and certain documents through the end of 2026, but the invoice itself, once issued after 1 January 2026, is denominated in euro only, not both.
• If part of your bookkeeping is still running "out of habit" in lev, check whether your invoicing system has fully switched to euro. Mixing both currencies in the same period is a common source of errors in the VAT ledgers.

You don't need to memorize any of this

That's a lot of rules: a ten-digit number, a 5-day deadline, when a credit note applies, euro instead of lev. The truth is you don't need to hold any of it in your head every time you sit down to bill a client.

Boiled down: an invoice for every taxable supply (or on request, if you're not VAT-registered), carrying every requisite under Art. 114, issued within 5 days of delivery, in euro from 2026 onward. If you get something wrong, a notice to the invoice, not a deletion or a manual fix.

Useful next reads:

What invoicing looks like with FreeMe.bg
How VAT and tax filing will work with FreeMe.bg
Selling to business clients in the EU? See how VAT-free invoicing works

FreeMe.bg numbers your invoices automatically, tracks the 5-day deadline, issues notices when something needs correcting, and runs entirely in euro, so you don't have to memorize a single article of the law. Log in with your Google account and issue your first correct invoice today.