> ## Documentation Index
> Fetch the complete documentation index at: https://developers.paylinedata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Build with Payline

> Create Applications through the API and let merchants complete and sign securely.

> [!WARNING]
>
> Confirm your invitation, environment and enabled capabilities with Payline before
> sending requests. Production requires separate Payline approval; documentation
> availability does not activate API access.

The Applications API supports Full Standard/Fiserv Applications with Owner 1 as
the sole signer. Create an Application with partial or complete merchant data,
send its handoff URL to the merchant, then poll for progress and retrieve current
data and immutable signed artifacts. Merchant documents, review, consent and
signature remain part of the merchant journey even with complete prefill.

**1. Get invited**

Payline provisions your partner access and invites engineers. Sign in to the
intended environment using the access link supplied by Payline. There is no
self-service onboarding prerequisite hidden in these guides.

**2. Obtain credentials**

An admitted organization manager uses **Account → Developer Settings** to
issue credentials. Keep the secret on your server. See [Credentials](https://developers.paylinedata.com/credentials.md).

**3. Create and complete**

[Create an Application](https://developers.paylinedata.com/create-applications.md) with a persisted request ID.
Use its URL for [merchant completion](https://developers.paylinedata.com/merchant-completion.md).

**4. Poll and retrieve**

[Poll status and retrieve data or artifacts](https://developers.paylinedata.com/retrieve-applications.md).
[Explicit reissue](https://developers.paylinedata.com/reissue-access.md) is available only for eligible unsigned access.

## Environments

| Environment | API base URL | Access |
| - | - | - |
| Sandbox | `https://sandbox.paylinedata.com/api/v1` | Invited partner, synthetic data, enabled capabilities |
| Production | `https://dashboard.paylinedata.com/api/v1` | Separate approval and environment-local credentials |

Use the environment and base URL shown in Developer Settings. Changing a URL
does not move credentials, sessions or data between environments. You may need to
sign in separately. Test access never implies Production access.

## Example verification

The guide examples were executed with synthetic data on **October 29, 2026**
against Sandbox release `25d8ae91f2a3d1253753fb1510fcc13269fe6bc3`.
The run covered eligible-user discovery, both creation examples (`ic_plus` and
the `surcharge` override), same-request recovery, handoff, status polling,
protected current-data retrieval, one explicit reissue, and one merchant
completion/signing flow with both signed-artifact downloads. Downloaded bytes
matched the stored artifact sizes and checksums, with committed access audits.

Coverage is limited to the shown examples on that release; other input/pricing
combinations and later releases require their own verification. Use your own
authorized Sandbox credential, fresh request IDs and synthetic data.

## Scope

The API provides creation, eligible allocation-user discovery, current handoff
recovery, status, full authorized retrieval, signed-artifact downloads and explicit
unsigned handoff reissue. It does not provide merchant-field updates, deletion,
document uploads, signing, processor submission or webhooks. Polling is the initial
integration model. Inspection UI availability is separate from this API guide.

The API reference is generated from the endpoint-owned OpenAPI definition. Open
the **API reference** tab for the exact request and response shapes. Examples here
are copyable; there is no interactive API playground.


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