Metal Detecting in Portugal

Last verified: October 2026.

Who this is for

• You own a metal detector, or plan to buy one, and want to know if you may use it here.
• You found something old in the ground, on a beach, or in a river and want to know what to do.
• You own land and someone has asked to search it with a detector.

Not for you if: you found a lost phone, wallet, or pet. Read What to Do If You Find or Lose Something in Portugal instead.

In Portugal you may not use a metal detector to search for objects of historical, artistic, coin, or archaeological interest. The only exception is a licence from Património Cultural, the national heritage institute. The licence lasts one year and is meant for scientific work, not for a hobby. If you find anything archaeological, by any means, you must report it within 48 hours to the heritage authority or the police. Using a detector without a licence can cost you a fine of about €2,494 to €4,988, plus the detector itself and anything you found.

What the law bans

The metal detector law has two bans.

1. Searching for old things. You may not use a metal detector to look for objects or artefacts that matter for history, art, coins (numismatics), or archaeology.
2. Carrying a detector onto protected sites. You may not use or even transport an unlicensed detector to search at monuments and archaeological sites that are classified, or in the process of being classified.

The second ban covers transport. Walking across a classified site with an unlicensed detector in your bag, even switched off, can break the law.

The heritage law adds a third rule. Using a metal detector, or any other detection equipment meant for archaeological research, needs a licence issued in advance.

The licence

The licence comes from Património Cultural, I. P., the public institute that protects Portugal's cultural heritage. It is based in Porto.

The institute decides each case on three points:

• what you want to achieve;
• the places you want to search;
• your scientific suitability (idoneidade científica).

That last point is the hard one. The licence is designed for archaeological research. There is no hobby licence and no general licence to search anywhere in the country.

What the application must contain

• Your identity.
• The purpose of the search.
• The exact places you want to search.
• The technical details of your detector.

The licence is valid for one year. No official fee, form, or processing time for it is published on the institute's website. Contact Património Cultural directly before you apply.

Archaeological work is a regulated activity. Excavations and surveys must be directed by an archaeologist and authorised by the heritage authority. In practice, the realistic way to use a detector legally is to join an authorised research project.

If you find something: the 48-hour rule

This rule applies to everyone, with or without a detector.

If you find any archaeological remains, on public or private land, or underwater, you must report the find within 48 hours. You can report it to:

• the heritage authority (Património Cultural); or
• the police (PSP or GNR), who keep the find safe and pass it on.

A police station counts, so you do not need to reach a heritage office. The 48 hours run from the moment you find the object.

A chance find, or one made while digging foundations or doing building work, is not illegal archaeological work. But you must still report it.

If a chance find has commercial value, the law gives you the right to a reward.

What to do, step by step

1. Stop digging. Leave the object where it is if you can.
2. Take photos of the object in place and of the spot.
3. Note the location, ideally with GPS coordinates.
4. Report it within 48 hours to the nearest PSP or GNR station or to Património Cultural.
5. Keep a copy of any report or receipt you are given.

Beaches, rivers, and other wet places

Finds in or near water follow the underwater heritage law. Its reach is wide. It covers:

• the territorial sea, its bed, and its shore;
• rivers, streams, lakes, and lagoons, with their beds and banks;
• quays and ditches;
• tidal waters in rivers and lakes;
• marshes, groundwater, wells, and reservoirs;
• areas that flood from time to time or are silted up, where the remains are nautical.

Objects washed up on the shore are included too. So a beach or a riverbank can fall under this law.

Who owns the find. Underwater heritage with no known owner belongs to the State. Anything its owner has not recovered within five years of losing or leaving it counts as having no known owner.

Reporting. If you find something, report it within 48 hours to:

• the customs office;
• the local maritime authority for that stretch of coast or water;
• any police authority; or
• the heritage authority directly.

The authority writes a find report (auto de achado fortuito). It records what you found, where, the date and time, and who you are. You have the right to a copy of the report and a receipt for the object. Ask for both.

If you report late. Unless you have a good reason, missing the 48 hours means you lose your rights as the finder. You can also be fined.

The reward. If the find is later added to the official inventory, the finder is entitled to half its value. For a whole archaeological site, the reward follows a table set by the government.

Building or dredging work. If dredging or digging turns up underwater heritage, the work must stop at once. The heritage authority has 10 days from receiving the find report to decide whether work may go on.

What the Civil Code says about treasure

The Civil Code has a general rule on treasure. If you find a hidden or buried object of some value and cannot find its owner, you keep half. The other half goes to the owner of the land or object where it was hidden.

To keep that right, you must announce the find or tell the authorities. The only exception is when the object was clearly hidden more than 20 years ago. If you hide the find from the landowner, or keep it knowing who owns it, your half goes to the State.

This rule does not help an unlicensed detectorist. If what you find is archaeological, the heritage laws apply, including the 48-hour duty. The full rules on ordinary lost property are in What to Do If You Find or Lose Something in Portugal.

Fines and other penalties

The laws still state their fines in escudos. The euro figures below use the fixed rate of 200.482 escudos to the euro.

Some other points:

• Negligence counts. Under the metal detector law, a careless breach is fined at half the amounts above. An attempt is also punished.
• You can lose the detector. The authorities can confiscate the detector you used and any archaeological, historical, artistic, or coin finds.
• Underwater breaches can also lead to the loss of boats and equipment, and a ban on the activity.
• Destroying remains is a crime. If you destroy archaeological remains by ignoring the rules, you face up to three years in prison or a fine.

What shops must tell you

The law puts duties on sellers, not buyers.

• Every advert for a metal detector must quote the ban and the penalties.
• The shop must give you a document with the same text when you buy.
• The packaging must carry a clearly visible warning in Portuguese.

If you bought a detector and got no such document, the shop broke the rules. That does not make your use of the detector legal.

Who enforces the rules

Património Cultural supervises the metal detector law, and you can send complaints to it. It applies the fines and confiscations. The PSP and GNR have general police powers. On beaches and inland waters, the maritime authority and customs also receive reports.

What this means for you

• If you want to use a detector legally, you need a licence from Património Cultural, with a stated purpose, named places, and proof of scientific suitability. In practice, join an authorised research project.
• If you want to search a beach for lost jewellery, a modern ring is not of historical or archaeological interest. But beaches and river banks fall under the underwater heritage law, and old coins turn up often. The moment you find something old, the 48-hour duty applies.
• If you are near a monument or archaeological site, do not bring an unlicensed detector at all. Ask Património Cultural or the town hall (câmara municipal) whether a site is classified.
• If you find something by chance, stop, photograph it, note the place, and report it within 48 hours.
• If someone asks to search your land, your permission does not replace the licence. Archaeological finds fall under the heritage laws, not the treasure rule.

Many outdoor activities in Portugal work the same way: banned unless you hold a specific permission. See Fishing in Portugal's Rivers and Reservoirs and Cutting Down a Tree on Your Own Land.

This guide is general information about Portuguese law, not legal advice. If you face a fine or a confiscation, speak to a lawyer.

Sources

This guide is written from official sources and, where relevant, organisations' own websites.

• Diário da República, Lei n.º 121/99, of 20 August (use of metal detectors), as listed by Património Cultural: https://files.diariodarepublica.pt/1s/1999/08/194a00/55275527.pdf (article 1 bans on searching and on use and transport at classified sites; article 2 licence, criteria, one-year validity, application contents; article 3 advertising, buyer's document, Portuguese warning; article 4 supervision and complaints; article 5 fines in escudos, negligence at half, attempt; article 6 loss of detector and finds; article 7 who applies fines), checked 2 October 2026
• Procuradoria-Geral Regional de Lisboa, Lei n.º 107/2001 (cultural heritage law), consolidated: https://www.pgdlisboa.pt/leis/lei_mostra_articulado.php?nid=844&tabela=leis (article 75(6) licence for detectors and detection equipment; article 77 archaeological works directed by archaeologists and authorised, chance finds excluded; article 78 48-hour notice to heritage authority or police, reward; article 103 destruction of remains, up to three years or 360 days' fine; article 105 fines for breaching articles 75(6) and 78(1)), checked 2 October 2026
• Procuradoria-Geral Regional de Lisboa, Decreto-Lei n.º 164/97 (underwater cultural heritage), consolidated: https://www.pgdlisboa.pt/leis/lei_mostra_articulado.php?nid=847&tabela=leis (article 1 scope including shores, rivers, tidal waters, wells, washed-up objects; article 2 State ownership and five-year rule; article 12 48-hour report and loss of rights; article 13 find report, copy and receipt; article 15 suspension of works, 10 days; article 17 reward of half the value; article 22 fines; article 24 loss of boats and equipment, activity ban), checked 2 October 2026
• Procuradoria-Geral Regional de Lisboa, Civil Code (Decreto-Lei n.º 47344/66), articles 1323 and 1324: https://www.pgdlisboa.pt/leis/lei_mostra_articulado.php?nid=775&tabela=leis (treasure split in half, duty to announce, 20-year exception, loss to the State), checked 2 October 2026
• Património Cultural, I. P., mission: https://www.patrimoniocultural.gov.pt/instituicao/missao/ (public institute for cultural heritage, created by Decreto-Lei n.º 78/2023, of 4 September; head office in Porto), checked 2 October 2026
• Património Cultural, I. P., archaeology legislation: https://www.patrimoniocultural.gov.pt/profissionais/arqueologia/legislacao/ (metal detector law and the Regulation of Archaeological Works, Decreto-Lei n.º 164/2014), checked 2 October 2026

Last verified October 2026. Rules and fees change; check the official source before acting.