How to bid for public tenders in Bulgaria

Bulgaria at a glance


Main law	Public Procurement Act (ZOP), 2016, consolidated to February 2026
Platform	CAIS EOP (app.eop.bg), mandatory for notices, documents and bids
Currency	Euro since 1 January 2026; lev amounts in the law are read in euro
National procedures from	EUR 51,129 goods and services; EUR 153,388 works
EU-level from	about EUR 140,000 goods and services; EUR 5.38 million works
Language	Bulgarian
Bid bond	None; performance guarantee up to 10%
Challenges	KZK within 10 days; award appeals suspend automatically

Where tenders appear

CAIS EOP. All procurement runs on one central electronic platform, CAIS EOP, operated by the Public Procurement Agency. Buyers and bidders use it for notices, documents, questions, bids and decisions, and its public search lists today’s procurements.
The register. Decisions and notices, including national-level ones, are published in the Public Procurement Register inside the platform.
TED. Notices at or above EU-level values go to TED through the platform.
Central purchasing. The Minister of Finance is the central purchasing body. A draft amendment would make buyers order nearly everything in its scope centrally from 2027.
Coming soon: 2027 plans. Since an August 2026 amendment, every buyer must publish its indicative 2027 procurement schedule on its CAIS EOP buyer profile by 30 November 2026. That gives bidders an early view of what’s coming.

Thresholds and procedures

Bulgaria joined the euro at 1 EUR = 1.95583 BGN. The law still states amounts in leva, and these are read as the converted euro amounts published by the Public Procurement Agency. Values exclude VAT.

Contract	Rule
Goods and services under EUR 25,565; works under EUR 40,903	Direct award allowed
Goods and services EUR 25,565–51,129; works EUR 40,903–153,388	Collection of offers, at least 10 days
Goods and services from EUR 51,129; works from EUR 153,388	Public competition (national), at least 20 days
Goods and services from EUR 139,998; works from EUR 5,381,918	EU-level procedures; published on TED
Utilities, goods and services	EU-level from EUR 430,993

One threshold for all buyers. The law applies the roughly EUR 140,000 goods-and-services threshold to all public buyers. It has no separate higher threshold for regional and local buyers.
Slightly behind the EU. The law’s EU-level figures still match the 2022–23 EU values, slightly below the 2026–27 figures (EUR 5,404,000 and EUR 140,000). We found no amendment updating them.
Time limits. At least 30 days for open procedures, or 15 with a prior notice or urgency. For restricted procedures, 30 days to ask to take part, then 25 to bid.
Questions. In EU-level procedures you can ask up to 10 days before the deadline, and the buyer must answer within 4 days.
Frameworks and lots. Framework agreements last up to 4 years (8 for utilities). Buyers must consider lots and explain if they don’t use them.

Who can bid

Foreign companies entitled to do the work in their home country can bid on the same terms. No bidder can be excluded for its status or legal form.
Consortia can bid without forming a company. The buyer can require winners to form one only if it said so, with reasons, when it opened the procedure.
Treaty partners and others.
- Covered countries: companies from WTO GPA and EU free-trade-agreement countries are protected.
- Everyone else: after the EU Court’s Kolin ruling (2024), companies from other countries can’t claim equal treatment, and each buyer decides whether to admit them. We found no Bulgarian guidance on this.
Offshore companies. A separate Bulgarian law bars companies registered in preferential tax regimes, and companies they control, from public procurement, with some exceptions. Our sources on its current exceptions are dated.
Language. Applications and tenders must be in Bulgarian, unless the work is performed abroad.
Proving eligibility.
- ESPD. You self-declare in the electronic European Single Procurement Document (ESPD), with one for each consortium member, subcontractor and company whose capacity you rely on.
- Certificates. The winner provides home-country certificates, or a sworn declaration where none are issued.
- Tax debts. Small tax or social-security debts (up to 1% of turnover and about EUR 25,565) don’t exclude you.
Construction. Larger works may only be done by builders entered in the Central Professional Register of the Builder, kept by the Bulgarian Construction Chamber. We couldn’t confirm whether EU and EEA builders must register or can rely on their home registration.

Bidding, step by step

Check eligibility: your home-country authorisation to do the work, your country’s treaty coverage, and the offshore rule.
Find tenders in the CAIS EOP public search, and on TED for EU-level contracts.
Get a qualified electronic signature and register your company in CAIS EOP. Foreign companies use the system on the same terms as Bulgarian ones.
Download the documents from the buyer’s profile, and ask questions in time: up to 10 days before the deadline at EU level, 5 days in public competition.
Prepare the ESPD in the platform or at espd.eop.bg.
Write the bid in Bulgarian, with amounts in euro. Older financial figures in leva must also show the euro value.
Submit electronically before the deadline. Your bid is encrypted with a key pair you generate, so keep the private key: if it’s lost, your bid can’t be opened.
If your price looks abnormally low, you have 5 days to justify it.
After the award, the standstill and the appeal window run (see below). Before signing, provide your certificates, the performance guarantee and any licences.

Guarantees and payment

No bid bond. The Act has no tender or participation guarantee.
Performance guarantee. It’s optional for the buyer and capped at 10% of the contract value (2% for contracts reserved for social enterprises). You choose the form: cash, a bank guarantee, or insurance, which is allowed only up to about EUR 255,646.
Payment. Public buyers pay within 30 days, extendable to 60 days by agreement if objectively justified. Our source for this is from 2020, so check the contract.
E-invoicing. Buyers must accept e-invoices in the European standard (EN 16931), and the platform can be used to send them. Contracts signed since 1 January 2026 are in euro.

How bids are evaluated

Best value. Contracts go to the most economically advantageous tender, judged on lowest price, cost (including life-cycle cost), or the best price-quality ratio.
Abnormally low bids. If your price is more than 20% better than the average of the other bids (with three or more bids), the buyer must ask you to justify it within 5 days. Bids that breach environmental, social or labour rules are rejected.
Green and social rules. Green criteria are mandatory for some supplies and services. Since 30 June 2026, wind-energy tenders must include EU sustainability requirements. Some contracts are reserved for social enterprises.

Challenging a decision

Where. Complaints go to the Commission for Protection of Competition (KZK), in Bulgarian.
Deadline. 10 days, generally from notification of the decision you’re challenging.
Standstill. The contract can’t be signed until 14 days after the award notice, except for single bids and some negotiated procedures.
Suspension. An appeal against the award decision automatically suspends the procedure, unless the KZK allows it to continue. Other appeals suspend it only if you ask for interim measures.
Timing. The KZK decides within 1 month for EU-level contracts and 15 days for others.
Fees. About EUR 435 for contracts up to about EUR 511,000, EUR 869 up to about EUR 2.56 million, and EUR 2,301 above that. These are converted from the lev tariff; the official euro amounts weren’t confirmed.
Court. You can appeal to the Supreme Administrative Court within 14 days. The fee is the same, and its decision, within a month, is final.

What changed in 2025–2026

July 2025: the EU confirmed Bulgaria’s euro adoption. A ZOP amendment updated the criminal exclusion grounds, in force from 31 January 2026.
December 2025: the Public Procurement Agency published the euro value of every amount in the Act. Procedures already opened in leva stay valid.
1 January 2026: the euro became legal tender, and the new EU thresholds took effect.
February and June 2026: amendments changed the definitions linked to conflicts of interest.
30 June 2026: EU sustainability requirements for wind-energy procurement began to apply.
August 2026: an amendment required every buyer to publish a 2027 procurement schedule by 30 November 2026, with fines for those that don’t.
Under discussion:
- Central purchasing: a draft to tighten central purchasing from 2027.
- EU reform: the European Commission’s September 2026 proposal for a single EU procurement regulation.

Live Bulgarian tenders

Questions

Do I need a Bulgarian company to bid on Bulgarian public tenders?

No. Any foreign company or person entitled to do the work in its home country can bid, and a bidder can’t be excluded for its legal form. A consortium needs no legal form to bid; the buyer may require the winners to form a company only if it said so, with reasons, when it opened the procedure.

Can I bid in English in Bulgaria?

Generally no. Applications and tenders must be in Bulgarian, unless the work is performed abroad and the buyer allows that country’s language. Complaints to the Commission for Protection of Competition must also be in Bulgarian, so budget for translation.

How do I submit a bid in Bulgaria?

Only electronically through the centralised platform CAIS EOP. You need a qualified electronic signature to register, and you prepare your bid and ESPD there. Bids are encrypted with a key you generate: lose the private key and your bid can’t be opened.

Do Bulgarian tenders require a bid bond?

No. The Public Procurement Act has no tender guarantee. The winner may have to give a performance guarantee of up to 10% of the contract value, as cash, a bank guarantee or, up to about EUR 255,600, insurance.

How quickly are suppliers paid in Bulgaria?

Public buyers pay within 30 days, extendable to 60 days by agreement if objectively justified. Buyers must accept e-invoices in the European standard, and contracts are now in euro.

How do I challenge a Bulgarian tender award?

Appeal to the Commission for Protection of Competition within 10 days. An appeal against the award decision automatically suspends the procedure. The fee is about EUR 435 to EUR 2,301 depending on the contract value, and the Commission’s decision can be appealed to the Supreme Administrative Court within 14 days.

Sources

This guide explains the rules in plain English; it isn’t legal advice. Procurement rules change, and each tender document sets its own conditions — it always prevails.