E-invoicing in Bulgaria: how an online store issues e-invoices

In short: an e-invoice is an invoice your store issues and sends electronically, for example as a PDF by email. The Bulgarian VAT Act accepts it on equal terms with paper when the customer agrees to receive it electronically, and it carries the same details required by Art. 114. It is due within 5 days of the sale, and in CloudCart it is issued automatically once the order is paid or fulfilled.

This guide is for merchants who sell in or from Bulgaria, including foreign founders and companies run from abroad, and for EU sellers who need to know what is changing across the Union. It is written by the team behind CloudCart, the Bulgarian ecommerce platform. The legal rules come from the consolidated Bulgarian VAT Act on lex.bg (in Bulgarian), and the EU timeline from the European Commission's page on ViDA. This is not accounting advice: your accountant confirms what applies to your company.

Note: if you are looking for the e-billing portal of your electricity, water or phone provider, that is run by the provider itself. This guide is about the invoices your online store issues to its customers.

What is an e-invoice, and is it valid without a signature?

An electronic invoice is an invoice that is issued, sent and received in electronic form. Under Art. 112(2) of the Bulgarian VAT Act, tax documents may be issued by hand or by software, and under Art. 114(6) an invoice may be on paper or electronic. The required details are the same for both.

Three rules in the Act apply only to electronic invoices:

• The customer's consent. Under Art. 114(9), you may document sales with electronic invoices and notes when the recipient accepts them, by written or tacit consent.
• The issue date. Under Art. 113(12), an electronic invoice counts as issued on the date it is made available to the customer so that they can receive it. For an online store, that is usually the date of the email with the PDF.
• Authenticity and integrity. Under Art. 114(6) and (10), the issuer ensures the origin, integrity and legibility of the invoice until the end of the retention period, through business controls that create a reliable audit trail between the invoice and the supply. A qualified electronic signature (QES) and electronic data interchange are listed in Art. 114(11) only as examples.

A signature and a company stamp are not among the required details in Art. 114(1). An invoice generated by the store's system is tied to a specific order, payment and delivery, and that link is the audit trail. Foreign owners who are used to stamped paperwork often ask about this first: a PDF without a stamp is a valid invoice in Bulgaria.

At EU level the term also has a narrower meaning. The EU business portal Your Europe describes an eInvoice as an invoice issued, sent and received in a structured way, so that software can process it automatically, and points to the European standard EN 16931. This structured format is where the ViDA rules are heading (see ViDA and the EU timeline).

What must an invoice contain under the Bulgarian VAT Act?

An invoice must contain 14 details listed in Art. 114(1) of the VAT Act, and from Jan 1, 2026 the taxable amount and the VAT are stated in euro (Art. 114(5)), after Bulgaria adopted the euro. Amounts may also be shown in another currency, as long as the taxable amount and the tax appear in euro. The table doubles as a sample invoice: the third column shows a filled-in invoice from an online store for one product with delivery.

Detail (Art. 114(1))	What it says	Example
(1) Document name	"Invoice" (or "Credit note", "Debit note")	Invoice
(2) Number	Sequential, exactly 10 Arabic digits, unique within the series	0000000187
(3) Issue date	The date the invoice is issued	The day of the order
(4) and (5) Supplier	Name, address, VAT number, or UIC (the company ID, EIK in Bulgarian) if the company is not VAT-registered	Shop EOOD, Plovdiv, 1 Example St, BG123456789
(7) and (8) Recipient	Name, address and ID number (VAT number, UIC, or for an individual the EGN or LNCh personal number)	Firma EOOD, Sofia, UIC 987654321
(9) Goods or service	Type and quantity	Ceramic mug, 2 pcs; Delivery to a courier office, 1 pc
(10) Tax point date	The date of delivery or of the payment received	The day of payment
(11) Price and taxable amount	Unit price excluding VAT, taxable amount and any discounts not already in the price	€10.00 each; delivery €5.00; taxable amount €25.00
(12) VAT rate	The rate, or the legal ground for 0% or no VAT	20%
(13) VAT amount	The amount of tax	€5.00
(14) Amount payable	When it differs from taxable amount plus VAT	€30.00
(15) New means of transport	Only for intra-EU supplies of new vehicles	left blank

Item 6 of Art. 114(1) has been repealed, which is why the numbering runs to 15 while there are 14 details. Two exceptions come up often in online retail:

• Simplified invoice up to €100. Under Art. 114(7), an invoice may leave out items 12, 14 and 15 when the taxable amount and the VAT together do not exceed €100, except for sales taxed in another EU country, intra-EU supplies and distance sales. Small businesses under the special scheme of Chapter 21b may leave out the same items regardless of the amount (Art. 114(7)(1)).
• A company without VAT registration. Under Art. 113(9), a company that is not VAT-registered may not charge VAT on its invoices. It issues invoices without VAT, identified by its UIC. When registration becomes mandatory is covered in the guide to VAT registration for an online store.

Electronic or paper invoice: what is different for an online store?

Electronic and paper invoices have the same required details and the same deadlines. They differ in the number of copies, the issue date and how they are stored.

Question	Paper invoice	Electronic invoice	VAT Act article
Copies	At least two: one for the supplier, one for the recipient	One file that both sides receive	Art. 113(2)
Consent needed	No	Yes, written or tacit	Art. 114(9)
Issue date	The date on the document	When it is made available to the customer, for example emailed	Art. 113(12)
Signature and stamp	Not a required detail	Not a required detail	Art. 114(1)
Origin and integrity	Business controls	Business controls, electronic signature or electronic data interchange	Art. 114(10) and (11)
Storage	In the original form	In the original form, with the data that prove origin and integrity	Art. 121

Under Art. 121(1), issued and received tax documents are kept until 5 years after the limitation period for the obligation they support has expired. For electronic invoices, Art. 121(2) also requires you to keep the data that prove their origin and integrity. In practice, keep each PDF linked to the order it came from.

How long do you have to issue an invoice? 5 days from the sale

An invoice is issued no later than 5 days after the tax point, and for an advance payment no later than 5 days after the money is received. This is Art. 113(4) of the VAT Act. For goods sold to a VAT-registered business in another EU country (an intra-EU supply), the deadline is the 15th of the following month (Art. 113(5)).

For an online store, the advance payment rule matters most: with a card payment the money arrives before the parcel ships. A store that issues the invoice at payment meets the deadline in both cases.

Do you have to issue an invoice to a private individual?

An invoice to a private individual who is not a trader is optional, but you issue one if the customer asks for it. Under Art. 113(3)(1) of the VAT Act, an invoice may be omitted when the recipient is an individual who is not a taxable person. Under Art. 113(6), however, when an invoice is optional it is issued at the request of the supplier or the recipient.

An invoice to an individual has the same details. As the recipient's ID number under Art. 114(1)(8), you state the number under Art. 84 of the Tax and Social Insurance Procedure Code, and under Art. 84(2) of that Code (in Bulgarian) individuals without a trade register or BULSTAT entry are identified by their EGN (Bulgarian personal number) or LNCh (the personal number of a foreigner).

The invoice does not replace the sales document under Ordinance N-18, Bulgaria's reporting rules for online sales. A fiscal receipt, or the sales document for an online card payment (the receipt Ordinance N-18 requires instead of a fiscal receipt), is issued for every sale, whether or not the customer also wants an invoice. Which document each payment method needs is set out in the guide to Ordinance N-18 for online stores.

In CloudCart the invoice takes its details from the order's billing address. In Settings → Invoicing, the switch "Issue an invoice only if a billing address is selected" is on by default: an order without a billing address gets no invoice. A store that sells mainly to consumers therefore invoices only the customers who asked for it at checkout. If an individual asks for an invoice with their EGN, agree with your accountant how to enter it and check the PDF with a test order.

What is a proforma invoice, and when do you issue one?

A proforma invoice is a preliminary document with the price and terms of the deal, which the seller sends before payment, usually so the customer can pay by bank transfer. It is not a tax document: under Art. 112(1) of the VAT Act, the only tax documents are the invoice, the note to an invoice (credit or debit note) and the protocol.

• A proforma gives no right to deduct VAT. A business customer cannot reclaim VAT on it, so they will ask for a proper invoice.
• A proforma does not change the invoice deadline. Once the money arrives, the payment is an advance and the invoice is due within 5 days (Art. 113(4)).
• A proforma has no required details or numbering. It helps to label it clearly "Proforma invoice" and add the order number, so nobody mistakes it for an invoice and the payment is easy to match.

An online store mostly needs proformas for business customers who pay by bank transfer after their own accounts team approves it. CloudCart's built-in invoicing issues invoices and credit notes; it has no separate proforma document. For a B2B sale paid by bank transfer, the invoice goes out when you mark the order as paid, which keeps it within the legal deadline from the day of payment. Group prices and payment by invoice for business customers only are on the B2B sales page.

	Proforma invoice	Invoice	Credit note
Tax document under Art. 112	No	Yes	Yes
When it is issued	Before payment, optional	Within 5 days of delivery or advance payment	Within 5 days of the return or reduction
Required details	None	Art. 114(1)	Art. 114 plus the invoice number and date and the reason (Art. 115(4))
VAT deduction for the customer	No	Yes	Reduces it

How do you fix a wrong invoice? Cancellation, protocol and credit note

An issued invoice cannot be edited: under Art. 116(1) of the VAT Act, corrections and additions are not allowed, so the wrong document is cancelled and a new one is issued. If the wrong invoice is already recorded in the books of the supplier or the recipient, Art. 116(4) requires a cancellation protocol for each side. The protocol states the reason, the number and date of the cancelled and the new document, and the signatures of the people who drew it up.

Cancellation is for a mistake in the document itself. When there is no mistake but the amount changes, for example the customer returns goods or gets a discount after the purchase, you issue a credit note under Art. 115. It is issued within 5 days of that event and states the number and date of the invoice it relates to.

In CloudCart the invoice locks the order: once it has a number, the products and prices on it cannot be edited, and the number stays for good. You create the credit note from the order (the View credit note button), and for a partial return from the return itself. The steps, the credit note numbering and the case of an invoice from a previous month are in the guide to credit notes and invoices in CloudCart. Withdrawal and return deadlines are covered in the guide to returns and consumer rights.

How does a CloudCart store issue e-invoices?

In CloudCart the electronic invoice comes from the order itself: the store creates a PDF with the next 10-digit number and emails it to the customer. Invoicing is included in every plan and you set it up once.

1. Turn on invoicing. Open Settings → Invoicing and switch on Activate invoicing.
2. Choose when the invoice is issued. In Generate Invoice, choose Automatic so it goes out on its own. With Manual you issue it with a button on the order, and the number can be sequential, typed in by hand or taken from external software (Gensoft).
3. Fill in your company details. On the Invoice template tab, click the block with the company details. For a company from Bulgaria the UIC (checked for a valid checksum) and the managing person (MOL) are required. The invoice logo is uploaded in the brand settings.
4. Set the numbering. Keep the zero padding at 10 digits and do not add a prefix or suffix with letters or dashes: under Art. 114(1)(2) of the VAT Act the number has ten digits and contains Arabic numerals only. Credit notes have their own separate sequence.
5. Add the company fields to checkout. In Settings → Cart and checkout, Company info block, choose which of the fields company name, VAT number, UIC and MOL are required. With Validate VAT number from VIES service, EU VAT numbers are checked against VIES, the EU's VAT number register.
6. Place a test order. Order to your own email and check the details from the table above in the PDF. The customer receives the invoice by email every time one is issued.
7. Send the invoices to your accountant. In the Invoices menu, Download saves the PDFs as a ZIP archive, and Export gives a CSV register in which credit notes have negative amounts.

Add a sentence to your store's terms and conditions saying that invoices are sent by email. That records the consent under Art. 114(9), and the customer knows where to look for the invoice.

The invoice is issued automatically when the order becomes Paid or Completed, when it is Fulfilled, or right away if the order contains only digital products. A cash on delivery order gets its invoice once it is fulfilled or marked as paid. The document numbers also go into the monthly XML file under Ordinance N-18, built by the N18 Audit app. The features themselves are on the Invoices and N-18 page, and how an order moves through its statuses is on the Orders and returns page.

ViDA and mandatory e-invoicing in the EU: what is coming and when

ViDA (VAT in the Digital Age) is the EU package that phases in structured electronic invoicing and digital reporting of transactions through January 2035. It was adopted on March 11, 2025 and consists of Directive (EU) 2025/516, Regulation (EU) 2025/517 and Implementing Regulation (EU) 2025/518, according to the European Commission.

Date	What applies	Does it affect an online store?
April 14, 2025	Member States may introduce mandatory e-invoicing under specific conditions	Only if Bulgaria (or the country where your company is registered) brings in such a rule by law
January 1, 2027	Minor clarifications for users of the OSS and IOSS schemes	Yes, if you sell to consumers in other EU countries through OSS
July 1, 2028	Single VAT Registration: an extended OSS and a mandatory reverse charge for non-established suppliers	Yes, if you sell in another EU country
July 1, 2030	Digital reporting requirements based on e-invoices, mainly for cross-border B2B supplies	Yes, if you sell to businesses in other EU countries
January 1, 2035	Deadline for Member States to align national real-time reporting systems with the EU model	Indirectly, through national rules

The current text of the Bulgarian VAT Act on lex.bg allows electronic invoices with the recipient's consent and does not require stores to issue structured e-invoices for sales in Bulgaria. We found no date for a national mandate in the Act, so we do not give one. Your accountant is the right person to follow changes to the VAT Act for you.

Some EU countries already have national systems. A store whose company is registered in Romania can invoice through the SmartBill app in CloudCart, which sends each invoice to ANAF's e-Factura system at the moment it is issued. A store run by a Hungarian company can use the Számlázz.hu app, which assigns the invoice number and reports every invoice and credit note to NAV, Hungary's real-time invoice system. When one of these apps is active, it becomes the store's invoicing provider in place of the built-in invoicing.

Get the store ready now: collect business customers' details in separate fields (name, UIC, VAT number, MOL), check EU VAT numbers in VIES at checkout, keep one number sequence, and give your accountant the CSV register together with the PDFs.

Frequently asked questions

Starting out? See how to create an online store step by step and the CloudCart plan prices; CloudCart takes 0% commission on your sales. Questions about invoices in your store: support@cloudcart.com.