Before you start

Legal residence in Portugal (a NIF and proof of address)
Your original, valid foreign driving licence
An electronic medical certificate from a doctor in Portugal (sent directly to IMT)
For non-EU licences: confirmation of whether your country has a reciprocity agreement with Portugal

Step-by-step

1
Get the electronic medical certificate
A registered doctor in Portugal issues a digital medical certificate (atestado medico) and sends it electronically to IMT - no paper to carry. Required for standard Group 1 categories (A, A1, AM, B, BE). Higher categories (C, D, etc.) also need a psychological assessment.
In personWho: You (via a doctor/clinic)Same day; certificate valid ~3 monthsAround EUR 30-50
2
Confirm your route (EU vs non-EU)
EU/EEA licences are valid until they expire - you simply register your address within 60 days and can exchange when convenient (lifetime-validity licences must be exchanged within 2 years). Non-EU: if your country has a reciprocity agreement, you exchange without a test within 2 years of residence; if not, you must take a Portuguese driving test for each category you hold.
OnlineWho: YouCheck before applying-
3
Apply via the IMT Online portal
Start the exchange on the IMTonline portal: fill the form and upload your documents (passport/ID, residence proof, your foreign licence). You then receive instructions by email for payment and for capturing biometric data (photo and signature). An in-person IMT desk visit is the alternative if you prefer.
OnlineWho: YouForm online; processing variesEUR 30 exchange fee
4
Biometrics, payment, and collection (or sit the test)
Provide biometric data and pay the fee as instructed; the Portuguese licence (carta de conducao) is then produced. If your country has no agreement, you instead book and pass the driving test (about EUR 30 per category) before the licence is issued. Note: you must generally start the exchange within 90 days of becoming resident to avoid being forced into a test.
In personWho: YouDirect exchange: a few weeks. Test route: longer.Included in the EUR 30 fee; driving test ~EUR 30/category if required

Documents you’ll need

Original valid foreign driving licence
Passport / residence document
NIF and proof of address in Portugal
Electronic medical certificate (sent by your doctor to IMT)
Passport-style photo / biometric data
For non-agreement countries: declaration of authenticity of the licence from the issuing/consular authority

Things most newcomers don’t know

EU/EEA licence holders can relax - non-EU holders should move fast.

An EU/EEA licence stays valid until it expires, so there is no rush beyond registering your address. A non-EU licence generally must be exchanged within 90 days of residence or you risk being pushed into a full driving test.

Source: gov.pt / IMT

Reciprocity agreement or not - that one fact decides everything.

Holders from agreement countries swap without a test within 2 years; everyone else sits a Portuguese exam per category. Check your country's status before you pay for anything, because it changes the cost and timeline entirely.

Source: gov.pt / IMT

The medical certificate is digital and short-lived.

Your doctor sends it straight to IMT electronically, so there is no paper to lose - but it is only valid around 3 months, so do not get it months before you actually apply.

Source: IMT / provider consensus

You can start the whole thing online via IMTonline.

Many people assume they must queue at an IMT desk. The exchange begins on the IMT Online portal; you only attend in person for biometrics/payment, which saves a trip.

Source: gov.pt / IMT

Common mistakes to avoid

Missing the ~90-day window for a non-EU licence and being forced to take a driving test
Getting the medical certificate too early and letting its ~3-month validity lapse
Assuming your country has a reciprocity agreement without checking - it may not
Driving on the foreign licence long after becoming resident, risking fines and invalid insurance