Overview
This guide explains how to edit PDF forms in Adobe Acrobat to prepare them for e-signature in Merchant Central. You’ll learn how to add and configure form fields, set up signature and email fields for one or more signers, and control which fields are required, editable, or read-only.
It also covers optional signatures, static information, file upload fields, and signer-specific or calculated fields. Properly configured PDF fields help ensure that information can be mapped from Merchant Central and that signers can complete the document as intended.
Editing PDF Forms
To prepare a PDF for e-signature, add the necessary text fields and checkboxes to the form.
- Open the PDF in Adobe Acrobat.
- Click Tools → Prepare Form.
- Use the Form Components sidebar to add text fields and checkboxes to the PDF.
To view or update a field’s settings, right-click the field and select Properties. You can change its name, appearance, and other settings.
To resize a field, drag one of its corners or edges.
Basic familiarity with PDF form editing is recommended. For guidance, see Adobe’s PDF form field basics guide.
If the PDF does not contain both a signature field and an email field, Adobe automatically adds a blank page with these fields when the e-signature document is generated.
Merchant Central can map lead information only to PDF text fields and checkboxes. Other field types, including radio buttons and dropdowns, are not supported for mapping. Replace unsupported fields with text fields or checkboxes as needed.
Adobe Sign does not support JavaScript embedded in PDFs or field-level calculations saved in field properties. Instead, use Adobe Sign text tags to define processing rules, such as calculating the sum of two fields when the e-signature application is generated.
Adding Adobe Signer Fields
Signer fields are standard PDF text fields with specific naming conventions that identify the signer and the required information.
These fields also indicate whether the document requires one signer or multiple signers.
When a signer selects a signature field, a window opens for them to enter their electronic signature.
A similar window appears when a signer selects an initials field.
The four most common signer fields are:
-
Signature:
signer1_es_:signer1:signature -
Email:
signer1_es_:signer1:email -
Date:
signer1_es_:signer1:date -
Initials:
signer1_es_:signer1:initials
To add a signature field for the first signer:
- Right-click the relevant PDF text field and select Properties.
- On the General tab, enter
signer1_es_:signer1:signaturein the Name field. - Save your changes.
Repeat these steps for the signer’s email, date, initials, and any other required fields.
The PDF must contain at least one email field and one signature field for the first signer.
You can copy a signature field to other sections or pages if the merchant needs to sign or initial the document in multiple places.
Configuring Multiple Signers
For a second signer, use the following field names:
-
Signature:
signer2_es_:signer2:signature -
Email:
signer2_es_:signer2:email -
Date:
signer2_es_:signer2:date -
Initials:
signer2_es_:signer2:initials
To configure additional signers, update the signer number in each field name. For example:
signer3_es_:signer3:signaturesigner4_es_:signer4:signature
Important: Every signer must have at least one signature field and one email field.
For a multi-signer application, add at least one signature field and one email field for each signer. Otherwise, Adobe treats the application as a single-signer document.
The example below shows signature, email, and date fields configured for two signers.
If a signer needs to sign in multiple places, copy and paste the corresponding signature fields.
Add initials fields wherever a signer needs to initial the document.
The order of signing is determined by the placement of signature fields in the PDF. Adobe sends the document to the first signer, then to each subsequent signer after the previous signer has completed it.
Configuring Optional Signature Fields
Some signatures, such as those for personal guarantees, may be optional. To make a signature field optional, use this naming format:
signer1_es_:signer1:opt signature
The opt designation marks the signature field as optional.
For more supported signer fields, see the Adobe documentation.
Configuring Editable, Read-Only, and Required Fields
You can configure whether signers can edit a field or must complete it before submitting the document.
- Right-click a PDF form field and select Properties.
- On the General tab, select Read Only or Required, as appropriate.
- Read Only: The field can be populated with lead information, but the signer cannot change it. Use this setting for pricing and other information the merchant must not modify. If left unchecked, the signer will be able to modify the field's value or enter a new one.
- Required: The signer must complete the field before submitting the document. Examples include Social Security number (SSN) and Federal Tax ID fields.
Hardcoding Static Fields
Information that remains the same across applications does not need to be mapped to lead data. Examples include fixed rates, fees, ISO information, and standard agreement terms.
You can enter these fixed values in either of two ways:
- Enter the values in the relevant PDF form fields, set the fields to read-only, and leave them unmapped.
- Open the PDF in editing mode and add the information directly to its pages.
Adding File Upload Fields
You can allow signers to upload supporting documents, such as driver’s licences or bank statements, as part of an e-signature application.
File uploads require specific PDF field naming conventions.
For instructions, see Enabling File Uploads in E-Signature Apps.
Adding Reserved or Calculated Fields
To make a PDF field editable by a specific signer only, add a signer-specific suffix to its name.
For example, to reserve the home_address field for the second signer, use this field name:
home_address_es_:signer2
The field is read-only when the first signer opens the document.
After the first signer signs, the document is sent to the second signer, who can edit the reserved field.
To reserve fields for other signers, use suffixes such as:
_es_:signer3_es_:signer4
Calculated fields automatically compute values from information entered elsewhere in the document.
For example, to calculate the total sales volume across three card brands, create a calculated field with this name:
signer1_es_:signer1:calc(visa_vol+mc_vol+discover_vol)
This example assumes the source PDF fields are named visa_vol, mc_vol, and discover_vol.