> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.withpersona.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.withpersona.com/_mcp/server.

# Prefilling Fields

> Prefill Inquiry fields through Hosted Flow query parameters.

Use the `fields` parameter to dynamically preset inquiry field values. In addition, `fields` will also prefill form values.

All attributes are optional. You only need to include keys for form fields you want prefilled. Individuals can still edit attributes after they're prefilled.

See [Inquiry Fields](/inquiry-fields) for more information.

**`curl`**

```curl curl
https://inquiry.withpersona.com/verify?inquiry-template-id=itmpl_JAZjHuAT738Q63BdgCuEJQre&fields[name-first]=Jane&fields[name-last]=Doe&fields[birthdate]=1957-05-29&fields[address-street-1]=132%20Second%20St.&fields[address-city]=San%20Francisco&fields[address-subdivision]=California&fields[address-postal-code]=93441&fields[address-country-code]=US&fields[phone-number]=+14151231234&fields[email-address]=janedoe%40gmail.com
```

> **Warning**
>
> #### Field values and customers
>
> Using the `fields` query string parameter is intended as a convenience for the end user in a manner similar to browser autofill. Because the query string values are handled client-side, they can be freely modified by the end user.
>
> If you must guarantee that field values are unmodified by the end user, you must use the external API to set the field values ahead of time.

> **Warning**
>
> #### Encoding passed values
>
> The `fields` value should be an object encoded as a string using a library like [qs](https://github.com/ljharb/qs#parsing-objects).
>
> If manually passing values, please be sure to make values URL-safe, e.g. with `encodeURIComponent` in JavaScript. For example, if passing a phone number with an area code, `'%2B1...'` should be passed instead of `'+1...'`.

> **Warning**
>
> #### Phone numbers
>
> Please ensure that phone numbers are properly formatted based on the number's country code. For example, US-based phone numbers should include the prefix `+1`.

For additional guidance on prefilling fields, see our [Help Center](https://help.withpersona.com/articles/79Y8gi2c0QnOzDax63LfDF/).