Defining a different amount for the first installment(s)

You wish to define a recurring payment for which the amount of the first installment would differ from the one set in the vads_sub_amount field.

Example: to define a recurring payment with the first 3 installments of 25 euros and the rest of the installments of 30 euros.

To do this:

  1. Use the fields required for your use case subscription with a fixed date and amount) to create your payment form.
  2. Use the fields below:
    Table 1. List of fields to define a different amount for the first installments
    Field name Value


    vads_sub_init_amount_number 3
    vads_sub_init_amount 2500
    vads_sub_amount 3000
  3. Compute the value of the signature field using all the fields of your form starting with vads_ (see chapter Computing the signature).
Example of a payment form
<form method="POST" action="">
<input type="hidden" name="vads_action_mode" value="INTERACTIVE" />
<input type="hidden" name="vads_amount" value="2990" /> 
<input type="hidden" name="vads_capture_delay" value="0" /> 
<input type="hidden" name="vads_ctx_mode" value="TEST" /> 
<input type="hidden" name="vads_currency" value="978" /> 
<input type="hidden" name="vads_cust_country" value="FR" /> 
<input type="hidden" name="vads_cust_email" value="" />
<input type="hidden" name="vads_cust_first_name" value="Paul" /> 
<input type="hidden" name="vads_cust_last_name" value="Juve" /> 
<input type="hidden" name="vads_cust_title" value="Mr" /> 
<input type="hidden" name="vads_page_action" value="REGISTER_SUBSCRIBE" /> 
<input type="hidden" name="vads_payment_config" value="SINGLE" /> 
<input type="hidden" name="vads_site_id" value="91335531" /> 
<input type="hidden" name="vads_trans_date" value="20140716080441" /> 
<input type="hidden" name="vads_trans_id" value="362812" /> 
<input type="hidden" name="vads_validation_mode" value="0" /> 
<input type="hidden" name="vads_sub_currency" value="978" /> 
<input type="hidden" name="vads_sub_init_amount_number" value="3" /> 
<input type="hidden" name="vads_sub_init_amount" value="2500" /> 
<input type="hidden" name="vads_sub_amount" value="3000" /> 
<input type="hidden" name="vads_version" value="V2" />
<input type="hidden" name="signature" value="86b2a17b9a5fcefb6c0120c57b25ec86ad1704ee"/>
<input type="submit" name="pay" value="Pay"/>