Custom SMS sender name

SMS Sender ID — your brand name on every text

Set a custom SMS sender ID so customers see your brand name instead of a number. Up to 11 characters, checked by Line, sent through the SMS API.

How your SMS will appear

MyBusiness

Text message

Hi! Your appointment is confirmed for tomorrow at 10am. Reply to reschedule.

10/11

Free to try · No credit card needed

From £4/mo · 8p per SMS · No contracts

Set up your SMS sender ID in 3 steps

1

Sign up for Line

Create a Line account and choose your UK number. Your number also serves as your fallback sender for two-way messages.

2

Request your sender ID

In Settings → API, enter your sender name: 3 to 11 letters, numbers or spaces. Line approves it after a check that the name is yours.

3

Send branded texts

Send through the SMS API with your sender name in the from field. Recipients in the UK and Ireland see your brand name as the sender.

When to use a custom SMS sender. When your brand name matters more than a reply.

Use sender IDs for one-way notifications and your UK number for two-way conversations.

Marketing campaigns

Send promotional texts with your brand name as the sender. 'AcmeSale: 20% off this weekend' looks professional and trustworthy.

Transactional notifications

Order confirmations, delivery alerts, and payment receipts with your brand name build customer confidence in the message.

Appointment reminders

Patients and customers are more likely to act on a reminder from 'YourClinic' than from an unknown number they might ignore.

Security and OTP codes

Verification texts sent with a recognisable sender name improve trust and reduce the chance of customers dismissing them as spam.

SMS sender ID features

Custom brand name

Set your business name (up to 11 characters) as the sender ID. Recipients see 'AcmeCorp' or 'YourClinic' instead of a random number.

Professional appearance

Branded sender IDs look more professional and trustworthy. Customers immediately know who the text is from — no guessing.

UK and international delivery

Alphanumeric sender IDs are supported on all major UK networks. International delivery depends on destination country rules.

Ofcom compliant

Using a recognisable brand sender ID is best practice under Ofcom guidelines. Customers can always identify who texted them.

Checked by Line

Request your sender name in Settings → API. Line checks it is your own business name before you send with it, so nobody else can use it to imitate you.

One-way vs two-way

Note: alphanumeric sender IDs are one-way. Recipients cannot reply to a brand name. For two-way conversations, use your dedicated UK number instead.

SMS sender ID FAQ

What is an SMS sender ID?

An SMS sender ID (also called an alpha sender ID or alphanumeric sender ID) is the name or number that appears as the sender when someone receives your text message. Instead of seeing a random mobile number, recipients see a branded name like 'AcmeCorp' or 'MyClinic' — up to 11 alphanumeric characters. Each send chooses its sender: your UK number or an approved sender name.

What is the difference between a sender ID and a phone number?

A phone number sender allows two-way SMS — recipients can reply and their message comes back to you. An alphanumeric sender ID is one-way only: recipients see your brand name but cannot reply. For customer notifications, marketing, and alerts where you do not need replies, a sender ID looks more professional. For conversations and support, use a real UK phone number.

How long can an SMS sender ID be?

An alphanumeric SMS sender ID can be 3 to 11 characters — letters, numbers and spaces, with no special characters. Examples: 'MyBusiness' (10 chars), 'AcmeCorp' (8 chars), 'Clinic123' (9 chars). If you need a longer brand name, abbreviate it or use a recognisable shortened version.

Are SMS sender IDs regulated in the UK?

Yes. Ofcom and the ICO have rules around SMS sender IDs in the UK. You cannot impersonate another business or use a misleading sender ID. Your sender ID should clearly identify your business. Using your brand name is always acceptable. Using a competitor's name or a misleading word is not. Line's acceptable use policy prohibits misuse of sender IDs.

Can I use an alphanumeric sender ID for two-way messaging?

No. Alphanumeric sender IDs are one-way only — recipients cannot reply to a brand name. For two-way customer conversations, you need a real UK phone number. With Line, you can use both: send one-way notifications with your sender ID, and have two-way conversations from your UK number in the shared inbox.

Do I need to register my sender ID in the UK?

In the UK, alphanumeric sender IDs do not currently require pre-registration in the same way as in some other countries (like the US A2P 10DLC registration). However, mobile networks may filter messages from unrecognised or suspicious sender IDs. Using your genuine business name and following PECR/GDPR rules for marketing texts is the correct approach.

Set up your SMS sender ID today

Send branded texts with your business name as the sender. From £4/month — no contracts.

  • Custom alphanumeric sender ID
  • Up to 11 characters
  • UK network delivery
  • Use alongside your UK number
  • One-way notifications
  • Two-way replies via your UK number
  • No contracts or minimum spend
  • From £4/mo
Set Up Your Sender ID

From £4/mo. Prices exclude VAT. Full pricing

Also available: SMS delivery reports · Virtual SMS number