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Earthquakes in Bulgaria

Bulgaria has catalogued 36 M4+ earthquakes since 2005 (ranked 112th of 187 countries), with the strongest reaching magnitude M7.1.

Bulgaria ranks 112th of 187 countries by catalogued seismic activity - a country with limited but non-zero seismic activity, averaging about 2 M4+ events a year alongside 7 significant M6+ earthquakes since 1900. The M6+ record here is thin - 7 events in all, so a single quake moves every figure on this page.

36
M4+ events (since 2005)
7
Major M6+ (since 1900)
M7.1
Strongest
~2
M4+ per year

The verdict

Bulgaria is below the global median in catalogued seismic activity, with 36 M4+ earthquakes logged since 2005 and 7 major M6+ events since 1900, the strongest reaching magnitude 7.1.

1904
busiest year (2 major events)
14 km
average recorded event depth
100%
of events are shallow (<70 km, the most damaging kind)

Average catalogued magnitude is 4.3 - most events are moderate M4-5 tremors that are felt but rarely cause damage. On the M4+ activity ladder Malaysia sits immediately above at 37 events and Bhutan sits immediately below at 35.

Where Bulgaria sits in the catalog

Rank 112th of 187 tracked countries (40th percentile by M4+ count since 2005). On the M4+ activity ladder Malaysia sits immediately above at 37 events and Bhutan sits immediately below at 35.

  • Malaysia - next more active (37 M4+)
  • Bhutan - next less active (35 M4+)

Same M4+ count, broken by peak magnitude

2 tracked countries share Bulgaria's exact count of 36 M4+ events since 2005. Among that cohort, Bulgaria ranks 2nd of 2 by strongest recorded magnitude (M5.0).

Country M4+ count Strongest
Libya 36 M5.2
Bulgaria (this page) 36 M5.0

Major (M6+) earthquakes in Bulgaria by year

Count of significant (magnitude 6.0+) events catalogued each year

Value

What this shows Bulgaria's most active year for major earthquakes was 1904 (2 M6+ events). Major-quake counts are irregular, they track the episodic release of tectonic stress, not a smooth trend.

Source USGS Comprehensive Earthquake Catalog (ComCat) As of 2005–present
0%100%0%
Share of Bulgaria's M4+ catalog that reached significant M6+ severity

0 of 36 catalogued M4+ events since 2005 reached M6.0 or higher.

Magnitude distribution of major events

Breakdown of the 7 significant (M6+) earthquakes on record for Bulgaria.

How the 7 total breaks down by magnitude M6.0-6.9 is the largest share -- 57.1%

M7.0-7.9

3

42.9%

M6.0-6.9

4

57.1%

Depth of major earthquakes

Hypocentral depth of the 7 M6+ events, shallow quakes shake the surface hardest. Average depth: 14 km.

Bulgaria100%Shallow (<70 km)Intermediate (70-300 km)Deep (>300 km)
Depth distribution of Bulgaria's M6+ events, USGS ComCat

Shallow (<70 km)

7

100.0% of events

Intermediate (70–300 km)

0

0.0% of events

Deep (>300 km)

0

0.0% of events

Strongest earthquakes in Bulgaria

The 7 most powerful events on record (USGS, since 1900).

Mag Location Depth
7.1 3 km W of Brezovo, Bulgaria 10.0 km
7.1 9 km S of Stara Zagora, Bulgaria 10.0 km
7.0 7 km SE of Stara Kresna, Bulgaria 15.0 km
6.8 6 km W of Stara Kresna, Bulgaria 15.0 km
6.7 5 km NNE of Lyaskovets, Bulgaria 15.0 km
6.1 15 km NE of Bobov Dol, Bulgaria 15.0 km
6.1 11 km ENE of Elhovo, Bulgaria 15.0 km

Significant earthquake record (7 events)

Every catalogued magnitude-6.0-and-above earthquake in Bulgaria since 1900, most recent first.

Mag Location Depth
7.1 3 km W of Brezovo, Bulgaria 10.0 km
7.1 9 km S of Stara Zagora, Bulgaria 10.0 km
6.7 5 km NNE of Lyaskovets, Bulgaria 15.0 km
6.1 11 km ENE of Elhovo, Bulgaria 15.0 km
6.1 15 km NE of Bobov Dol, Bulgaria 15.0 km
7.0 7 km SE of Stara Kresna, Bulgaria 15.0 km
6.8 6 km W of Stara Kresna, Bulgaria 15.0 km

Frequently asked questions

How many earthquakes have occurred in Bulgaria?
The USGS catalog records 36 earthquakes of magnitude 4.0 or greater in Bulgaria since 2005, an average of about 2 per year. Separately, 7 significant (M6+) earthquakes are catalogued back to 1900.
What was the strongest earthquake in Bulgaria?
The strongest catalogued earthquake in Bulgaria measured magnitude 7.1. Across the full M4+ catalog the average magnitude is 4.3 - most earthquakes are moderate.
How seismically active is Bulgaria?
By catalogued M4+ activity, Bulgaria ranks 112th of 187 countries worldwide - a country with limited but non-zero seismic activity. Its busiest year for major (M6+) events was 1904, with 2.
How deep are earthquakes in Bulgaria?
Across the 7 major (M6+) events on record, the average depth is 14 km. 100% were shallow (under 70 km), where surface shaking is strongest at a given magnitude.
Where does this data come from?
Every figure is derived from the USGS Comprehensive Earthquake Catalog (ComCat). M4+ counts cover 2005 onward (the period of consistent global completeness); the significant-event series covers M6+ back to 1900. Nothing is modelled or estimated.

About Bulgaria's figures

36 M4+ events since 2005 · strongest M7.1 · average M4.3 · 7 M6+ significant events since 1900 · latest M4+ catalog stamp Apr 25, 2022. Computed from the USGS Comprehensive Earthquake Catalog (ComCat). See the methodology and USGS ComCat.

Disclaimer: PlainQuake is informational only, not an emergency service or engineering advice. See our full disclaimer.

What Bulgaria's numbers mean

Bulgaria ranks 112th of 187 countries tracked - a country with limited but non-zero seismic activity.

  • About 2 M4+ earthquakes strike Bulgaria per year on average, though major (M6+) activity is episodic - 1904 was the busiest year on record with 2 significant events. See the full country ranking
  • 100% of Bulgaria's catalogued major earthquakes are shallow (under 70km) - shallow events generally produce stronger surface shaking than deep ones of the same magnitude. How depth affects shaking
  • The strongest catalogued event reached M7.1. Compare against neighboring or similarly-ranked countries before drawing conclusions from magnitude alone. Compare strongest earthquakes

Figures reflect the USGS ComCat catalog (M4+ since 2005, M6+ significant events since 1900) - not a real-time hazard assessment. For official guidance, see the USGS Earthquake Hazards Program.

According to the US Geological Survey Earthquake Hazards Program, PlainQuake's figures are rendered directly from 315,341 recorded M4+ earthquakes and 14,428 significant M6+ events (USGS ComCat, 2005-present) -- no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-07-19.