Overview

Finnish mobile operators now require every sender and Sender ID that delivers SMS to Finnish networks to be authorised. This covers alphanumeric Sender IDs, Finnish and international long codes, and short codes. Operators approve or reject submissions under Traficom Regulation 28 and the industry Sender ID Code of Conduct.

Twilio submits your Sender IDs to the operators on your behalf through the operators' shared submission portal. You provide the information below through the Twilio Console. There is no Twilio fee for this authorisation.

Key dates

The operators and their downstream suppliers apply this treatment. Twilio does not block these messages. We recommend submitting your Sender IDs well before 2 November 2026 so they are approved in time.

Two registries: which one do you need?

Finland has two separate registries.

Most customers only need the mandatory authorisation. Choose the protected registry only if you want exclusive rights to a Sender ID.

Mandatory authorisation (all customers)

What you need to provide

1. Business Registration Document. An official copy of your business registration or brand registration certificate.
2. Contact person. Name, email address and phone number. The operators do not collect these, but Twilio must keep them on file.

Sender ID requirements

• 1 to 11 characters
• Permitted characters: A-Z, a-z, 0-9 and spaces
• No leading, trailing or consecutive spaces
• The characters å, ä and ö may not display correctly on all routes

Operators review each Sender ID manually. A Sender ID is approved when it is your name, trademark, established domain or a recognisable abbreviation of these, and is closely connected to your lawful business. It is rejected if it is misleading, offensive, or protected by another sender in Traficom's registry.

How to register

1. Compile the Alphanumeric and Numeric Sender IDs you currently use to send to Finland.
2. Gather your Business Registration Document.
3. Submit the business document through the Alphanumeric Sender ID registration page in the Twilio Console.

What happens next

1. Twilio reviews your submission. We check that your business can be verified in an official register or public sources, that your website is live and matches the business, that the Sender ID is linked to your business, and that the Sender ID is not protected by another brand in Traficom's list.
2. If something is missing or incorrect, we email the address you gave for notifications with the reason. Correct the submission in the Console and resubmit.
3. Once Twilio approves your submission, we send it to the operators.
4. If the operators do not reject it, the Sender ID is set up on your account (and on your subaccounts, if you selected them). If an operator rejects it, we email you.

Traficom protected registry (optional, paid)

The protected registry gives you exclusive rights to an alphanumeric Sender ID. Traficom charges its own registry fee, paid directly to Traficom. Twilio's fee is separate and covers supporting the protected Sender ID on our routes.

1. Register the Sender ID with Traficom.
2. Confirm the Sender ID appears on Traficom's protected list. 
3. Contact Twilio at senderid-notify@twilio.com with the signed Letter of Authorization (LOA) and we will confirm the Twilio fee (70 USD per month plus a one-time 375 USD setup fee).
4. Twilio completes the protected registration for your Account SID.
5. Twilio also submits the Sender ID through the mandatory authorisation described above, so it is confirmed as authorised.

Rules for protected Sender IDs at Twilio

• Each Account SID supports one protected Sender ID.
• If you have several protected Sender IDs, create one subaccount for each and register each separately.
• After registration, all traffic on that Account SID is sent with the protected Sender ID. If you also send non-protected Sender IDs from the same account, move that traffic to a separate account first. Otherwise those Sender IDs are overwritten with the protected one.

Frequently asked questions

Do I have to register my Sender ID? 

Yes. From 4 May 2026, operators overwrite unregistered Sender IDs with "Tuntematon". From 2 November 2026, unregistered alphanumeric Sender IDs are changed to "Roskaposti" and unidentified Finnish numbers are blocked.

Is there a fee? 

The mandatory authorisation is free. Only the optional Traficom protected registry carries a Twilio fee of 70 USD per month plus a one-time 375 USD setup fee.

Can another company be approved for the same Sender ID? 

Under the mandatory authorisation, yes. The same Sender ID can be approved for several senders. Only a Traficom protected Sender ID is exclusive.

I already registered a protected Sender ID with Traficom. Do I register again with Twilio? Will I be charged twice? 

Yes, you still register with Twilio so we can support it on our routes. Follow the protected registry steps above. Traficom's fee is paid to Traficom. Twilio's fee is separate and covers support on our routes.

Can I keep sending to Finland from a US long code without registering it? 

No. The requirement applies to international long codes as well. An unregistered US long code is already shown as "Tuntematon" and may be blocked from 2 November 2026. 

Does the requirement apply to messages other than SMS? 

Operators also override SMS, MMS and RCS arriving from the public international interface with an alphanumeric Sender ID, and block or overwrite numeric ones.

My Sender ID was rejected. What should I do? 

We email you the reason. Correct the information and resubmit through the Twilio Console.