Collecting information at checkout

Most products need something from the buyer before you can deliver — an address, artwork notes, a name to print, the email a licence belongs to. Those questions are set per product, under customer fields in the product editor.

Field types

Type	Use it for
Text	Names, references, free notes.
Number	Quantities and measurements where only a number makes sense.
Email	Addresses. Validated as an email, so typos are caught at checkout rather than at delivery.
Checkbox	Yes or no — an agreement, an opt-in, a flag.
Select	A fixed list you supply. Always better than free text where the answer must be one of a known set.

PREFER SELECT OVER TEXT

A size asked as free text comes back as "L", "Large", "lge" and "large-ish". A select gives you data you can act on without cleaning it first.

Once per order, or once per unit

This is set on the variant, not the product, with Collect fields per unit.

Setting	The buyer is asked	Right for
Off	Once for the whole order.	Delivery address, PO number, artwork notes.
On	Once for every unit ordered.	The email for each licence, the name and size for each shirt, the dietary requirement for each dinner place.

Per-unit answers are what fill the Register, so anything you will later need as a list of named people has to be collected this way.

Validation

Fields can be constrained so bad answers are refused at checkout rather than discovered later:

Required — the buyer cannot complete the order without it.
Allowed or blocked email domains — restrict licences to the brand's own domain, or block personal addresses.
Unique — stop the same value being used twice, so two seats cannot be issued against one address.
Pattern and length — enforce a format where one genuinely exists.
Admin only — a field the buyer never sees, for your team to complete.

Locking an answer after purchase

Some answers can be marked locked, so they cannot be edited once the order is placed.

LOCK ANYTHING THAT IS THE THING BEING SOLD

Where a licence is issued against an email address, letting that address be edited later quietly moves the licence to a different person — with no purchase, no record, and no charge. Lock it.

Ask for less

Every extra required field is another reason an order is abandoned or answered carelessly. Ask only for what you cannot deliver without, mark the rest optional, and get anything else afterwards from the people who actually need it.