For now we only have EE, Vodafone UK and Three UK tested. CMLink May also be able to use. Feel free to submit your findings.

In your config, add UK Wi-Fi Calling in [Proxy Group] section:

UK Wi-Fi Calling = select, DIRECT, UK

Then enclose this in your [Rules] section:

# Wi-Fi Calling
RULE-SET,https://ghp.ous50.moe/https://raw.githubusercontent.com/ous50/Surge/refs/heads/master/wifi-calling/uk.conf,UK Wi-Fi Calling

Remember to set include-all-networks=true and include-cellular-services=true