The Bulgarian National Science Fund (BNSF; Bulgarian: Фонд “Научни изследвания”, FNI) is Bulgaria’s national competitive research-funding agency. It operates under the Ministry of Education and Science pursuant to the Law on the Promotion of Scientific Research (adopted 2003), and has run open competitive calls since 2008. For research administrators and international researchers evaluating Bulgarian funding or collaboration opportunities, BNSF/FNI is the primary national entry point — comparable in national role to Croatia’s HRZZ, Poland’s NCN, or the Czech Republic’s GAČR in the Central/Southeast European funding landscape.
Role and governance
BNSF/FNI’s governing structure separates policy decisions from day-to-day operations: an Executive Council is the fund’s decision-making body, while a Chief Executive is responsible for implementation and coordination. Both are appointed by Bulgaria’s Minister of Education and Science. Proposals are assessed through peer review, organized into disciplinary panels (typically spanning physical sciences/engineering, life sciences, and social sciences/humanities), consistent with the standard national-funding-council model used across the EU.
Beyond its own national competitions, BNSF/FNI also functions as Bulgaria’s contact point for a number of multilateral funding mechanisms: it participates in Horizon Europe-adjacent joint calls (for example M-ERA.NET and CHIST-ERA), supports Bulgarian participation in European Research Council (ERC) and COST Action activity, and administers bilateral science-cooperation agreements with partner countries’ funding agencies.
Main funding instruments
BNSF/FNI runs several recurring national scientific programs rather than a single generic “research grant.” The instruments most relevant to a research administrator scoping Bulgarian funding include:
- Competitions for fundamental scientific research — BNSF/FNI’s core, recurring open call, funding investigator-led basic-research projects across disciplines. Budgets vary by call year; the 2025 competition, for example, was announced with an overall budget in the tens of millions of Bulgarian lev (BGN).
- VIHREN Programme (“Excellent Research and People for the Development of European Science”) — BNSF/FNI’s flagship excellence-track scheme, covered in detail below.
- “Petar Beron i NIE” (“Petar Beron and NIE”) Programme — a separate national scientific program specifically designed to accelerate the reintegration and career development, in Bulgarian higher-education institutions and research organizations, of experienced researchers with internationally recognized results. Where VIHREN is open to applicants of any nationality or residence, Petar Beron i NIE is the instrument most directly aimed at Bulgarian and Bulgaria-connected researchers actively relocating their research career back into a Bulgarian host institution.
- Bilateral and multilateral joint calls — co-funded competitions run jointly with partner-country agencies or European joint programming initiatives (e.g., M-ERA.NET for materials research, CHIST-ERA for ICT), plus support mechanisms for Bulgarian participants in COST Actions and Horizon Europe consortia.
All BNSF/FNI competitions require an eligible Bulgarian host organization (a university, research institute, or other accredited scientific organization) to administer the grant, even where the principal investigator is not Bulgarian or not resident in Bulgaria.
The VIHREN Programme in detail
VIHREN is BNSF/FNI’s excellence-track program, explicitly modeled on the profile of an ERC-caliber grant: it funds individual investigator-led projects on the strength of the researcher’s track record and the scientific ambition of the proposal, rather than through the fund’s standard fundamental-research competition.
Eligibility
Per BNSF/FNI’s own call documentation (via EURAXESS Bulgaria and fni.bg), VIHREN eligibility is deliberately broad on nationality and residence:
- Researchers working or living in Bulgaria or in any other country may apply — the call text states no age, sex, or nationality restrictions apply to the principal investigator.
- The application must be submitted jointly with a Bulgarian host organization, which administers the grant if awarded.
- Recent calls have given priority consideration to applicants of Bulgarian nationality, or applicants living in Bulgaria, who had previously applied for an ERC grant and scored Category B or higher at the first evaluation step without being funded — in effect, a mechanism for capturing near-miss ERC applicants with a Bulgarian connection.
This structure means VIHREN is genuinely open to non-Bulgarian principal investigators (provided a Bulgarian host institution is willing to administer the award), while its priority criteria and its practical applicant pool skew toward Bulgarian and Bulgaria-connected researchers — including diaspora scientists — who want to build or lead a research group at a Bulgarian institution. Researchers specifically seeking a reintegration-focused instrument rather than an ERC-style excellence grant should also review the Petar Beron i NIE program described above.
Grant schemes and funding levels
VIHREN is structured as two parallel grant schemes, evaluated by career stage rather than by discipline:
- Leading Researcher grant — for principal investigators already established as recognized research leaders. Documented calls have set a maximum budget of BGN 265,000 per year.
- Established Researcher grant — for principal investigators in the process of consolidating an independent research team or program. Documented calls have set a maximum budget of BGN 210,000 per year.
Both schemes fund projects for up to five years, with the total budget reduced pro rata for a shorter proposed duration. Under each disciplinary review panel, BNSF/FNI has typically funded one Leading Researcher and one Established Researcher award, subject to available budget for that call round — so the effective number of VIHREN awards per call is small and highly competitive.
Evaluation process
VIHREN uses a two-step peer review broadly parallel to ERC evaluation practice: proposals are assessed by disciplinary panels (physical sciences/engineering, life sciences, social sciences/humanities), and applicants who can document a qualifying near-miss ERC score at step 1 may be eligible to advance directly to step 2 of the BNSF/FNI evaluation.
Programme names, eligibility criteria, funding ceilings, and call timing change between rounds. The figures above reflect BNSF/FNI’s own published call documentation for the most recently documented VIHREN rounds; always confirm current eligibility, budget ceilings, and the open-call calendar directly against fni.bg and BNSF/FNI’s EURAXESS Bulgaria listings before preparing an application, since a new call round was not independently confirmed as open at the time of writing.
Practical guidance for international researchers
- You do not need Bulgarian nationality or residence to apply to VIHREN — but you do need a Bulgarian university, institute, or accredited research organization willing to serve as host and administer the award. Identifying and confirming a host institution’s willingness to participate is normally the first practical step, well before drafting a full proposal.
- Distinguish VIHREN from Petar Beron i NIE early. VIHREN is an ERC-style excellence grant open to any nationality; Petar Beron i NIE is specifically a reintegration/career-development instrument for experienced researchers moving their career into a Bulgarian institution. Diaspora researchers evaluating a return to Bulgaria should check both rather than assuming VIHREN is the only relevant route.
- Budget in BGN, not EUR. BNSF/FNI publishes and administers award ceilings in Bulgarian lev (BGN); confirm current EUR-equivalent figures separately when comparing against ERC or other EU-denominated schemes, since the lev is pegged to the euro but figures are not automatically interchangeable in call documentation.
- Use a prior ERC evaluation where you have one. If you (or a Bulgarian-connected co-applicant) previously scored Category B or higher at ERC step 1 without funding, that evaluation history may be directly relevant to VIHREN’s priority criteria and fast-track evaluation path — confirm current applicability against the live call text, since priority criteria have varied between rounds.
- Check call status directly with BNSF/FNI before planning around a specific deadline. BNSF/FNI runs VIHREN and its other national programs on an irregular multi-year cadence rather than a fixed annual calendar; the fund’s own site (fni.bg) and its EURAXESS Bulgaria notices are the authoritative source for whether a given program is currently open.
- Coordinate with your home institution’s sponsored-programs or international-collaboration office on award administration, subaward/host-institution agreements, and reporting expectations — the CASRAI grants-management pillar and the Office of Sponsored Programs entry cover the general institutional-administration side that applies regardless of which country’s funder is involved.
How BNSF/FNI compares to other national funders
BNSF/FNI is one of several national research-funding councils research administrators encounter when supporting international collaboration in Central, Eastern, and Southeast Europe. See also CASRAI’s overviews of HRZZ (Croatia), NCN (Poland), and GAČR (Czech Republic), as well as the broader Horizon Europe overview for EU-level funding that Bulgarian institutions and BNSF/FNI-funded researchers can access alongside national schemes.
Frequently asked questions
Is BNSF/FNI the same as the Bulgarian Academy of Sciences?
No. BNSF/FNI is Bulgaria’s national competitive research-funding agency, operating under the Ministry of Education and Science; the Bulgarian Academy of Sciences (BAS) is a separate national research and higher-education institution that, like Bulgarian universities, can itself apply for and host BNSF/FNI-funded projects.
Can a non-Bulgarian researcher lead a VIHREN grant?
Yes. BNSF/FNI’s published VIHREN call documentation states there are no age, sex, or nationality restrictions on the principal investigator, provided the project is submitted jointly with an eligible Bulgarian host organization that administers the award.
What is the difference between the Leading Researcher and Established Researcher VIHREN schemes?
The Leading Researcher scheme targets principal investigators already established as recognized research leaders; the Established Researcher scheme targets investigators still consolidating an independent research team or program. Documented calls have set higher annual funding ceilings for Leading Researcher awards (BGN 265,000/year) than for Established Researcher awards (BGN 210,000/year).
Does BNSF/FNI fund international collaborative projects, not just individual PI grants?
Yes, alongside VIHREN and its core fundamental-research competitions, BNSF/FNI co-funds bilateral projects with partner-country funding agencies and participates in multilateral joint calls such as M-ERA.NET and CHIST-ERA, as well as supporting Bulgarian participants in COST Actions and Horizon Europe consortia.
