Need to send a registered letter with proof of delivery to a tenant in Portugal, but you do not want to visit a CTT post office, wait in line, and still figure out exactly what to write? Good news: in 2026 you can do the whole thing online, in under 5 minutes, from anywhere in the world.
This guide explains how sending a registered letter online works in Portugal, what options exist, what the law requires, and when this method is legally valid. Two terms you will see throughout: CTT is the Portuguese postal service, and AR stands for aviso de receção, the signed proof-of-delivery slip that the recipient signs and CTT returns to the sender.
What is a registered letter with proof of delivery?
A registered letter with aviso de receção (AR) is a CTT service that guarantees two essential things:
- Registration: the letter has a tracking number and CTT records the delivery
- Proof of delivery: the recipient signs a slip that is returned to the sender as evidence of receipt
This combination is the only notification method with evidentiary value in Portuguese courts for tenancy matters. The NRAU (the Portuguese urban lease law) explicitly requires a registered letter with AR for formal communications between landlord and tenant, such as rent arrears notices, rent increases or lease terminations.
Send it now, no post office needed
At cartaregistada.pt you fill in the details, the letter is generated and sent by CTT with proof of delivery. No queues, no trips, works from any country. From €14.99.
Send a registered letter, €14.99Can I send a registered letter without going to a CTT post office?
Yes. There are currently two ways to do it without visiting a CTT shop in person:
Important note (July 2026): CTT itself does not offer fully online registered letters for individuals. As of July 2026, CTT's online service only generates the shipping paperwork (acceptance slip and label); you still have to finish the sending at a post office, as stated in CTT's official help pages (in Portuguese). For individuals, sending a registered letter with proof of delivery 100% online, with no contract, no software and no trip at all, only exists at cartaregistada.pt.
Option 1: An online sending platform with physical printing and delivery
It works like this: you submit the details online, the letter is printed and sent by CTT as a conventional registered letter with AR. The recipient receives a physical paper letter, signs the AR slip, and the proof is sent to you. cartaregistada.pt works exactly this way.
Option 2: Electronic notification
Some services offer electronic notifications claiming equivalent legal validity. Be careful: for tenancy matters governed by the NRAU, Portuguese law still requires a physical registered letter. An electronic notification without the tenant's prior consent may not be accepted in court.
How to send online: step by step
- Choose the type of letter. Rent arrears, rent increase, lease termination or another formal communication to your tenant.
- Fill in the details. Your details as landlord, the tenant's details and the lease specifics (address, rent amount, months owed, and so on).
- The letter is generated automatically. With legally sound wording and the references to the Portuguese Civil Code and the NRAU that apply to your case.
- You review and pay. The complete process costs €14.99, including drafting the letter and CTT sending with AR.
- CTT delivers. The letter is delivered to the tenant's address as a conventional registered letter with proof of delivery.
- You receive the proof. The delivery slip signed by the tenant is recorded so you can use it as evidence.
Registered letter online vs at the post office: comparison
| Criterion | Online (cartaregistada.pt) | In person (CTT shop) |
|---|---|---|
| Delivered by CTT with AR | ✓ Yes | ✓ Yes |
| Letter drafting included | ✓ Yes | ✗ You must bring the letter written |
| Wording based on the applicable law | ✓ Yes | ✗ You must prepare it yourself |
| No travel needed | ✓ Yes | ✗ You must go to the shop, in Portugal |
| Time required | ~5 minutes | 30–60 minutes |
| Cost | €14.99 | ~€3.50 (postage only, no drafting) |
| Available 24/7 | ✓ Yes | ✗ Shop opening hours |
Is a letter sent online delivered the same way?
Yes. The letter is sent by CTT exactly like a conventional registered letter with proof of delivery. The recipient receives a physical envelope, signs the delivery slip, and that proof is recorded. The delivery process is identical to a letter handed in at a CTT counter.
For specific questions about whether this method suits your case, for example in the context of court proceedings, we recommend consulting a lawyer.
What if the tenant does not collect the letter?
If the tenant does not collect the letter at CTT, it is returned to the sender marked "not collected" or "absent". Even so, the letter has legal value, as long as it was sent to the correct address stated in the lease agreement.
In that case, the recommended procedure is:
- Keep the proof of sending and the returned delivery slip
- Wait 30 to 60 days and send a new letter
- If the second letter is also not collected, it is deemed received on the 10th day after sending
What situations can I use a registered letter online for?
Online sending is suitable for all formal tenancy communications that require a registered letter with AR:
- Rent arrears: a formal demand to the tenant with a payment deadline
- Rent increase: notice of the new amount using the INE coefficient, the official Portuguese statistics index (mandatory 30 days in advance)
- Lease termination: formal notice of the intention to end the tenancy
- Opposing automatic renewal: notice that you do not intend to renew the lease
- Notice of sale of the property: the tenant's right of first refusal when the property is sold
Send your registered letter online
Already have the letter? Upload the PDF and we print it and send it through CTT with proof of delivery, no post office visit needed. €14.99 all inclusive.
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