Understanding UK, Australian, and New Zealand SMS sending numbers

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You will learn

Please note that only account Owners and Admins will have the ability to add/manage sending numbers.

Learn about sending numbers for the UK, Australia, and New Zealand, including what each can do and who can use them. 

Overview of features


Branded sender ID

Long code

Short code (vanity)

Available countries




(The same branded sender ID is used for both countries)






Plan needed

Free & paid




$0, included in all plans

$0, included in paid plans

UK: $1000/month




Verification process needed?


UK: No

AUS: Yes


Base throughput

10 mps

10 mps

100 mps

Can receive SMS

Double opt-in

Click-to-text forms


SMS conversations (two-way messaging)


Branded sender IDs

Branded sender IDs (also known as alphanumeric IDs) are the default option in Klaviyo for both the UK and Australia. The same branded sender ID is used in both countries. 

When using branded sender IDs, high-volume senders may need to request more throughput. Typically, we recommend reaching out to our Support team and asking for more throughput when you are sending more than 140,000 messages at time. 


A branded sender ID is best for your business if branding is important to you. This sending ID can be customized to fit your brand, so recipients always know who their messages are coming from.

There's also no verification process with branded sender IDs, so you can start sending immediately. 


The downside of this ID is that it cannot receive messages, so your recipients cannot text you back. This means that you cannot use the following Klaviyo functionality with a branded sender ID:

  • Click-to-text forms and email banners
  • Subscribe keywords
  • SMS conversations/two-way messaging
  • Double opt-in
  • Mobile support

Long codes

A long code is also only good for reaching subscribers in 1 specific country. If you have an Australian long code, you cannot use this number to send to anyone in the UK, US, or Canada. 

We recommend you request more throughput when you are sending around 140,000 messages at a time.


Long codes are able to receive inbound messages, which gives you more flexibility in what you can do with SMS. 

You will be able to use: 

  • Double opt-in
  • Click-to-text forms and email banners
  • Subscribe keywords
  • SMS conversation/two-way messaging
  • Mobile support

This allows your customers to opt-in using subscribe keywords, get 1-to-1 support, share their preferences and interests, etc.


Long codes are not branded. The number will look like any other number, and customers won’t automatically know who’s texting them. 

Also, in Australia, long codes must undergo a verification process. This process takes 1–3 business days, and you cannot send until the number is approved. 

What happens you have a long code and branded sender ID

If you have both a long code and branded sender ID, the long code always takes precedence over the brand. For example, if you have an Australian long code and a branded sender ID, the long code will deliver your messages to AUS recipients, while the brand will send only to those in the UK. 

Short code (vanity)

Short codes are only available in the UK and New Zealand. However, short codes for Australia are on our product roadmap!

If you plan to send to multiple countries, you will need to get a separate short code and have it approved for each new country where you want to send. Short codes only send to recipients in 1 specific country. For instance, if you have a short code for the UK, you cannot use the same short code in Australia, New Zealand, Canada, or the US. 

In New Zealand, short codes are the only number type available. If you want to collect or send to SMS subscribers in New Zealand, you must have an NZ short code.

Short codes are best for those who are high-volume senders. For example, if you want to send campaigns to 300,000 or more recipients, a short code is likely the best sending number for you. On the other hand, if you are mainly sending SMS via flows or through smaller, more segmented campaigns, a long code or brand ID is likely better. 

Not all businesses and industries are eligible for a short code. You must apply and be approved. This approval process takes several weeks, so even if you are eligible, you cannot instantly start sending from a short code. 

Additional resources

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