paypal recurring payments form

a3 - amount to billed each recurrencep3 - number of time periods between each recurrencet3 - time period (D=days, W=weeks, M=months, Y=years)<form action="https://www.paypal.com/cgi-bin/webscr" method="post"><input type="hidden" name="cmd" value="_xclick-subscriptions"><input type="hidden" name="business" value="me@mybusiness.com"><input type="hidden" name="currency_code" value="USD"><input type="hidden" name="no_shipping" value="1"><input type="image" src="http://www.paypal.com/en_US/i/btn/btn_subscribe_LG.gif" border="0" name="submit" alt="Make payments with PayPal - it's fast, free and secure!"><input type="hidden" name="a3" value="5.00"><input type="hidden" name="p3" value="1"> <input type="hidden" name="t3" value="M"><input type="hidden" name="src" value="1"><input type="hidden" name="sra" value="1"></form>

Mandatory fields are:

a3: Regular rate. This is the price of the subscription

p3: Regular billing cycle. This is the length of the billing cycle. Thenumber is modified by the regular billing cycle units (t3, below)

t3: Regular billing cycle units. This is the units of theregular billing cycle (p3, above) Acceptable values are: D (days),W (weeks), M (months), Y (years)

no_note: This field makes sure your subscriber is not prompted to include anote with the subscription, a function which PayPal Subscriptionsdoes not support. This field must be included, and the value mustbe set to 1.

Source:Subscriptions and recurring Payments Guidefrom PayPal.

It's important to note that without the optional field src (also described in the doc above) the subscription expires just after the first transaction and threfore it's not recurrent:

src: Recurring payments. If set to “1,” the payment will recur unlessyour customer cancels the subscription before the end of thebilling cycle. If omitted, the subscription payment will not recurat the end of the billing cycle.