Notification messages support twelve default template tags to provide information to your purchasers and administrators. You can add additional notification messages by using the My Tickets custom field api.

The content produced by some of these tags is simple strings, but others produce more complicated data. All of the tags automatically toggle their formats depending on whether you’re sending HTML or plaintext email.

A link to the user’s receipt.
For e-tickets or printable tickets, a list of the purchased tickets.
The purchaser’s name, as provided in the shopping cart.
The name of your site.
The purchase’s internal payment ID. (Probably only useful for admin messages!)
Purchase data: tickets purchased, how many, at what price.
The purchaser’s provided shipping address.
All transaction data from the payment gateway.
The payment gateway’s transaction ID.
For offline payments, the amount owed on the purchase.
The ticketing method chosen by the purchaser.

In general, I recommended that you at minimum provide your purchaser’s with their receipt link and their purchase data, regardless of the ticketing and payment methods you allow.