Prefilling email to target questions via URL parameters

When you share a link to a public email to target page, you can prefill the form by adding query parameters to the URL. This is useful when you already know something about the person you're linking - for example an email that includes their name, or a link from another system that knows which option they should pick.

Prefilled answers appear in the form as if the person had typed them. They can still review and change them before submitting.

Parameter format

Each parameter is named response_ followed by the question key:

https://your-movement-domain.com/p/your-flow-slug?response_name=Jane&response_email=jane%40example.com&response_postcode=ABC%20123

• name , email, and postcode are question keys (see Available question keys below).
• Values must be URL-encoded - e.g. spaces become %20, @ becomes %40.
• You can prefill any number of questions in one URL, joined with &.
• Prefill can be combined freely with other parameters such as UTM tags.

Available question keys

• postcode - The postcode to use for looking up the recipients
• name - The name of the submitter
• email - The email of the submitter
• address_1 - The first line of the submitter's address
• city - The city of the submitter
• opt_in - Whether to pre-check the opt-in parameter (true to check, defaults to unchecked)

Full example

An email to target page with a prefilled postcode, email, and checked opt-in:

https://your-movement-domain.com/p/email-your-mp?response_postcode=ABC%20123&response_email=jane%40example.com&response_opt_in=true

Limitations and further information

• Non-matching values are ignored silently. If the answer text for a multiple choice question doesn't exactly match one of the options, the question is left blank rather than showing an error.
• Prefilling happens in the visitor's browser as the page loads; nothing is stored until the person actually submits the form.