VAT for SaaS companies in Bulgaria: rules, OSS and reverse charge

For those considering to start a company in Bulgaria in the SaaS sector, VAT management is one of the most sensitive tax aspects. The sale of subscription-based software does not follow a single rule applicable to all customers, but varies depending on the nature of the buyer, their location and the type of service provided.

In general, a Bulgarian SaaS company may face very different scenarios. If it sells to an EU company with a valid VAT number, it will usually not apply Bulgarian VAT and will instead use the reverse charge mechanism. If it sells to a private consumer within the European Union, it must apply the VAT rate of the customer’s country, often through the OSS system. If the customer is based in Bulgaria, the standard Bulgarian VAT rate of 20% generally applies. For customers outside the EU, the treatment may vary and requires specific evaluation.

How VAT works for SaaS services in Bulgaria

SaaS services are generally classified as electronically supplied services. This means that VAT treatment depends not only on the location of the company, but primarily on the country where the customer is established.

In the case of Bulgarian customers, the SaaS company normally applies local VAT at 20%. For B2B transactions with businesses established in another EU Member State and holding a valid VAT number, the reverse charge mechanism applies: the invoice is issued without VAT and the customer accounts for the tax in their own country.

The situation is different for private EU consumers. In this case, VAT must be calculated according to the rate applicable in the customer’s country of residence. To simplify compliance, companies may use the OSS regime, which allows them to declare in Bulgaria the VAT due in other Member States, without opening a separate VAT position in each country.

To apply these rules correctly, it is essential to collect reliable customer data. For B2B transactions, the validity of the VAT number must be verified, for example through VIES. For B2C transactions, companies must retain evidence supporting the customer’s location, such as billing address, country of the payment method or IP address.

VAT for SaaS companies in Bulgaria: registration, invoicing and reporting obligations

A SaaS company established in Bulgaria must carefully monitor thresholds and situations that trigger VAT registration obligations. When significant taxable turnover is generated on the Bulgarian market, registration becomes mandatory. Certain cross-border transactions may also create obligations, regardless of overall turnover.

Voluntary registration may also be considered before reaching mandatory thresholds, especially if the company incurs significant costs in Bulgaria and wants to recover input VAT. However, this choice also involves additional administrative obligations, including periodic reporting, compliant invoicing and proper record-keeping.

Invoices must correctly include supplier and customer details, VAT numbers where applicable, a clear description of the SaaS service, the applicable VAT rate, the VAT amount where due, and the appropriate wording in cases of reverse charge. For intra-EU B2B transactions, it is essential to clearly indicate that the operation is subject to reverse charge.

The management of refunds, cancellations, downgrades and credit notes must also comply with VAT rules. Each adjustment must be linked to the original invoice and recorded in a traceable manner, to avoid inconsistencies in reporting.

Read also: EBITDA calculation in Bulgaria: why it is a key indicator for evaluating business performance

OSS regime, B2C sales and risks to avoid

The OSS regime is particularly relevant for SaaS companies that sell subscriptions to private consumers in multiple EU countries. Through this system, the company can declare in Bulgaria the VAT due in other Member States, while applying the correct VAT rate of the customer’s country.

This makes accurate configuration of payment and invoicing systems essential. It is not sufficient to rely automatically on payment gateways or accounting software: tax settings must be regularly reviewed, especially when the company sells to both businesses and consumers.

Among the most common errors are applying Bulgarian VAT to EU B2B clients with valid VAT numbers, failing to verify VAT numbers, misusing OSS for transactions that should be treated as B2B, or insufficiently documenting the customer’s location.

Another important aspect concerns sales through marketplaces or app stores. In some cases, the platform may be considered the deemed supplier and take responsibility for charging and paying VAT. However, the SaaS company must still retain documentation such as reports, contracts and records to distinguish direct sales from intermediary transactions.

For SaaS companies accepting cryptocurrency payments, the nature of the service does not change. VAT, when applicable, must be calculated on the value of the service expressed in fiat currency, with proper conversion into BGN and accurate documentation of the exchange rate used.

Read also: VIES in Bulgaria: general functioning and role in the European VAT system

Conclusion

Correct VAT management is not only about formal compliance, but also about the financial stability of the business.

Errors in customer classification, delays in reporting or incomplete documentation can lead to penalties, interest, tax audits and complications in relationships with investors, partners and authorities.

To properly structure the tax framework of a SaaS company—from VAT registration to OSS and reverse charge management—it is advisable to rely on experienced local professionals such as Accountancy Bulgaria, tax advisor in Bulgaria, who support entrepreneurs and companies in navigating the Bulgarian tax system.