Customizable Button Labels in the Signing View

The signing screen is the single most visible page any of your signers will see, and until now the buttons on it read exactly the way Firma.dev shipped them. As of 2026-06-24 that changes. Workspace admins can override the signing-view button labels, per language, across all nine supported languages. If your product calls it "Approve" instead of "Sign," the button can say Approve.

This is a white-label feature. It sits alongside custom email domains, notification control, and embedded signing as another layer of control over what your signers actually see. For the full picture, see the complete guide to building a white-label e-signature API.

What shipped

Workspace admins can now override the default button labels in the signing view. The overrides live on workspace settings and apply to the buttons a signer interacts with as they move through a document, including the primary sign action, the button that advances to the next required field, and the finish action that completes signing.

Labels are stored as signing_button_label_overrides, a JSON object keyed first by language and then by button key. Nothing about the signing logic changes. Only the text your signers read.

Why button copy matters in a white-label flow

When you white-label the signing experience, you control the logo, the colors, the email domain, and the sending address. Then a signer reaches the actual signing screen and hits a button labeled with generic copy that doesn't match anything else in your product. That single mismatch is enough to remind them they've left your app.

Button copy is a small surface with an outsized effect on how native the flow feels. Matching it to your own terminology closes one of the last visible gaps between your product and the underlying signing engine.

Per-language overrides

Overrides are set per language and apply across all nine supported languages: English, Spanish, Italian, Portuguese, French, German, Greek, Russian, and Polish. A signer viewing the flow in French sees your custom French labels. A signer in German sees your custom German labels. You set each language independently, so you can override only the languages you actively support and leave the rest on Firma.dev's defaults.

This pairs naturally with multi-language signatures. If you already localize the signing flow, custom button labels let you carry your own voice through every language you serve rather than accepting the default translation.

How it works

Set the overrides through the workspace settings endpoint. The signing_button_label_overrides field takes an object keyed by language code, then by button key:

curl -X PUT https://api.firma.dev/functions/v1/signing-request-api/workspace/{workspace_id}/settings \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "signing_button_label_overrides": {
      "en": {
        "sign": "Approve and Sign",
        "next": "Continue",
        "finish": "Complete Signing"
      },
      "es": {
        "sign": "Aprobar y Firmar",
        "next": "Continuar",
        "finish": "Completar Firma"
      }
    }
  }'

curl -X PUT https://api.firma.dev/functions/v1/signing-request-api/workspace/{workspace_id}/settings \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "signing_button_label_overrides": {
      "en": {
        "sign": "Approve and Sign",
        "next": "Continue",
        "finish": "Complete Signing"
      },
      "es": {
        "sign": "Aprobar y Firmar",
        "next": "Continuar",
        "finish": "Completar Firma"
      }
    }
  }'

curl -X PUT https://api.firma.dev/functions/v1/signing-request-api/workspace/{workspace_id}/settings \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "signing_button_label_overrides": {
      "en": {
        "sign": "Approve and Sign",
        "next": "Continue",
        "finish": "Complete Signing"
      },
      "es": {
        "sign": "Aprobar y Firmar",
        "next": "Continuar",
        "finish": "Completar Firma"
      }
    }
  }'

Signers see the customized labels immediately. To revert to Firma.dev's defaults, set the field to null:

curl -X PUT https://api.firma.dev/functions/v1/signing-request-api/workspace/{workspace_id}/settings \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "signing_button_label_overrides": null
  }'

curl -X PUT https://api.firma.dev/functions/v1/signing-request-api/workspace/{workspace_id}/settings \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "signing_button_label_overrides": null
  }'

curl -X PUT https://api.firma.dev/functions/v1/signing-request-api/workspace/{workspace_id}/settings \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "signing_button_label_overrides": null
  }'

A few validation rules worth knowing before you set values. Each label must be a string of 500 characters or less, language keys must be valid language codes, and any HTML tags or control characters are stripped automatically. One thing to keep in mind for multi-tenant setups: button label overrides are a workspace-level setting only, so if you run a seperate workspace per customer, each one carries its own labels. There is no company-level override that cascades down.

For the full reference, including every available button key, see the white-labeling guide in the docs.

Get started

Custom button labels are available now on every workspace, on the same pay-as-you-go pricing as everything else: €0.029 per envelope (about 3¢ USD), with no monthly minimums.

Get started with Firma.dev for free, no credit card required.