Gravity Forms.
Every Address field on every form, wired automatically.
Gravity Forms has a native Address field, so there is nothing to configure. The plugin detects every Address field on every form and attaches UK autocomplete to it.
Three steps.
Install the Postio plugin and activate it.
Go to Settings → Postio, paste your API key and press Save key.
Open any form containing a Gravity Forms Address field and start typing.
Details.
Works with the International address type as well as the UK one — only UK addresses are returned either way.
No CSS classes and no per-form setup.
Using something else?
UK address lookup on the block and classic checkout, plus My Account addresses. No configuration.
Automatic on WPForms Pro. On WPForms Lite, two minutes with CSS classes.
Native Address field, free core, wired automatically.
Native Address field with sub-inputs, free, wired automatically.
CF7 has no address field, so you tag yours. Two minutes, once per form.
No address field in Ninja Forms, so you tag yours. Two minutes, once per form.
Elementor Pro only. Tag your fields with CSS classes and you are done.
Ready in under a minute.
Sign up, grab a key, paste it in. Your first hundred lookups are on us.