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Country profile · USGS ComCat

Earthquakes in Portugal

Portugal has catalogued 423 M4+ earthquakes since 2005 (ranked 47th of 187 countries), with the strongest reaching magnitude M7.8.

Portugal ranks 47th of 187 countries by catalogued seismic activity - a moderately seismically active country, averaging about 20 M4+ events a year alongside 11 significant M6+ earthquakes since 1900. The record is episodic - 27% of those M6+ events fall in 1969 alone.

423
M4+ events (since 2005)
11
Major M6+ (since 1900)
M7.8
Strongest
~20
M4+ per year

The verdict

Portugal is moderately seismically active, above the global median, with 423 M4+ earthquakes logged since 2005 and 11 major M6+ events since 1900, the strongest reaching magnitude 7.8.

1969
busiest year (3 major events)
16 km
average recorded event depth
100%
of events are shallow (<70 km, the most damaging kind)

Average catalogued magnitude is 4.5 - most events are moderate M4-5 tremors that are felt but rarely cause damage. On the M4+ activity ladder Svalbard and Jan Mayen sits immediately above at 434 events and Tanzania sits immediately below at 368.

Where Portugal sits in the catalog

Rank 47th of 187 tracked countries (75th percentile by M4+ count since 2005). On the M4+ activity ladder Svalbard and Jan Mayen sits immediately above at 434 events and Tanzania sits immediately below at 368.

Portugal's M4+ count vs. every tracked country

Total catalogued M4+ events since 2005, USGS ComCat

423 Top 25% higher than 75% of 187 countries

0–500: 143 countries (76%). This entry sits in this band. 500–1,000: 11 countries (6%). Above this entry. 1,000–1,500: 5 countries (3%). Above this entry. 1,500–2,000: 5 countries (3%). Above this entry. 2,000–2,500: 1 countries (1%). Above this entry. 2,500–3,000: 1 countries (1%). Above this entry. 3,000–3,500: 2 countries (1%). Above this entry. 3,500–4,000: 1 countries (1%). Above this entry. 4,000–4,500: 3 countries (2%). Above this entry. 4,500–5,000: 3 countries (2%). Above this entry. 5,000–5,500: 12 countries (6%). Above this entry. Portugal 0 5,000+ every tracked country, bucketed by value

Each bar is a 500-wide band; taller bars hold more countries. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source USGS Comprehensive Earthquake Catalog (ComCat) · 2005-present

How Portugal compares to its nearest peers

Portugal ranks in the 75th percentile for M4+ frequency among all 187 tracked countries. Plotted here against its 20 nearest-ranked peers by how OFTEN they shake (M4+ count) against how HARD the strongest one ever hit (max recorded magnitude).

Portugal vs. its 20 nearest-ranked peer countries, USGS ComCat 2×2 strategic matrix plotting 21 entities by M4+ events since 2005 (X) and Strongest recorded magnitude (Y), with a crosshair dividing the plot into four quadrants. Frequent and severeRare but severeFrequent, capped so farLower on both axes 0200400600800 M5M6M7M8 M4+ events since 2005 Strongest recorded magnitude
Portugal vs. its 20 nearest-ranked peer countries, USGS ComCat
Read the chart (all 21 values)
Country M4+ events Strongest magnitude
Costa Rica 717 M7.6
Panama 704 M6.7
Nepal 694 M7.8
Micronesia 672 M6.6
Kyrgyzstan 625 M6.7
Italy 609 M6.6
Ethiopia 574 M5.9
Venezuela 531 M7.5
Dominican Republic 489 M5.8
Svalbard and Jan Mayen 434 M6.8
Portugal (this page) 423 M6.3
Tanzania 368 M6.0
Yemen 338 M6.6
Somalia 332 M5.8
Australia 285 M6.6
Albania 273 M6.4
Honduras 269 M7.5
Djibouti 260 M5.5
Algeria 245 M6.0
Mayotte 232 M5.9
Haiti 217 M7.2

Major (M6+) earthquakes in Portugal by year

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

Value

What this shows Portugal's most active year for major earthquakes was 1969 (3 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%0.7%
Share of Portugal's M4+ catalog that reached significant M6+ severity

3 of 423 catalogued M4+ events since 2005 reached M6.0 or higher.

Magnitude distribution of major events

Breakdown of the 11 significant (M6+) earthquakes on record for Portugal.

How the 11 total breaks down by magnitude M6.0-6.9 is the largest share -- 90.9%

M7.0-7.9

1

9.1%

M6.0-6.9

10

90.9%

Depth of major earthquakes

Hypocentral depth of the 11 M6+ events, shallow quakes shake the surface hardest. Average depth: 16 km.

Portugal100%Shallow (<70 km)Intermediate (70-300 km)Deep (>300 km)
Depth distribution of Portugal's M6+ events, USGS ComCat

Shallow (<70 km)

11

100.0% of events

Intermediate (70–300 km)

0

0.0% of events

Deep (>300 km)

0

0.0% of events

Strongest earthquakes in Portugal

The 10 most powerful events on record (USGS, since 1900).

Mag Location Depth
7.8 188 km SW of Sagres, Portugal 14.5 km
6.7 29 km NE of Ribeira Seca, Portugal 10.0 km
6.7 99 km SE of Senhora do Rosário, Portugal 10.0 km
6.6 91 km SSE of Olhão, Portugal 28.5 km
6.3 74 km SE of Povoação, Portugal 14.0 km
6.2 12 km N of Horta, Portugal 10.0 km
6.2 169 km WSW of Sagres, Portugal 10.0 km
6.1 82 km SE of Senhora do Rosário, Portugal 8.0 km
6.0 181 km SW of Sagres, Portugal 20.0 km
6.0 272 km W of Sagres, Portugal 45.0 km

Significant earthquake record (11 events)

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

Mag Location Depth
6.1 82 km SE of Senhora do Rosário, Portugal 8.0 km
6.3 74 km SE of Povoação, Portugal 14.0 km
6.0 181 km SW of Sagres, Portugal 20.0 km
6.2 12 km N of Horta, Portugal 10.0 km
6.7 29 km NE of Ribeira Seca, Portugal 10.0 km
6.0 272 km W of Sagres, Portugal 45.0 km
6.2 169 km WSW of Sagres, Portugal 10.0 km
7.8 188 km SW of Sagres, Portugal 14.5 km
6.6 91 km SSE of Olhão, Portugal 28.5 km
6.7 99 km SE of Senhora do Rosário, Portugal 10.0 km
6.0 2 km SW of Alcochete, Portugal 10.0 km

Frequently asked questions

How many earthquakes have occurred in Portugal?
The USGS catalog records 423 earthquakes of magnitude 4.0 or greater in Portugal since 2005, an average of about 20 per year. Separately, 11 significant (M6+) earthquakes are catalogued back to 1900.
What was the strongest earthquake in Portugal?
The strongest catalogued earthquake in Portugal measured magnitude 7.8. Across the full M4+ catalog the average magnitude is 4.5 - most earthquakes are moderate.
How seismically active is Portugal?
By catalogued M4+ activity, Portugal ranks 47th of 187 countries worldwide - a moderately seismically active country. Its busiest year for major (M6+) events was 1969, with 3.
How deep are earthquakes in Portugal?
Across the 11 major (M6+) events on record, the average depth is 16 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 Portugal's figures

423 M4+ events since 2005 · strongest M7.8 · average M4.5 · 11 M6+ significant events since 1900 · latest M4+ catalog stamp Jul 11, 2026. 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 Portugal's numbers mean

Portugal ranks 47th of 187 countries tracked - a moderately seismically active country.

  • About 20 M4+ earthquakes strike Portugal per year on average, though major (M6+) activity is episodic - 1969 was the busiest year on record with 3 significant events. See the full country ranking
  • 100% of Portugal'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 M7.8. 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.