If you make things to order, some days sell out and some don't. A delivery date picker lets customers choose when — but on its own it happily books 120 orders onto a Saturday you can only fulfill 50 of. Delivery capacity limits are what stop that: a cap on how many orders each date, and each time slot, can take.
The overbooking problem
Made-to-order merchants — bakeries, florists, meal-prep kitchens, furniture makers — have a hard daily ceiling. Shopify doesn't know about it, so it keeps accepting orders. You find out you're overbooked when you're already behind, and someone's Saturday cake isn't getting made.
Capacity limits move that ceiling into checkout, where it belongs.
How per-date and per-slot caps work
With OrderRules on the Advanced plan, each availability rule can carry:
- A cap per date — e.g. 50 deliveries on any given day.
- A cap per slot — e.g. 15 in the 14:00–16:00 window, so a single window can sell out without closing the whole day.
When a date or slot hits its cap, it greys out live on the storefront picker — customers simply can't choose it.
No overbooking, even at the last slot
Two shoppers checking out at once can't both grab the final slot. Booking is atomic: the OrderRules Shopify Function reserves the slot at checkout, so the count is always correct. And if an order is cancelled, its slot is released automatically and becomes bookable again — no manual bookkeeping.
Because enforcement is server-side, Shop Pay, Apple Pay, and direct checkout URLs can't sneak past the cap.
It's the same idea as order limits
Delivery capacity is just OrderRules' order-caps idea pointed at a future date. Your storewide "50 orders/day" cap and your "50 deliveries on Saturday" cap are the same number expressed two ways — which is exactly why they live in one app. More on that in Order limits + delivery scheduling: why they belong in one app.
Set it up
- Open Delivery → Availability rules and edit (or add) a rule.
- Set a capacity per date, and optionally a capacity per slot.
- Save. Full dates and slots grey out automatically; checkout blocks anything sold out.
Full detail: Delivery capacity limits · Time slots.
Ready to cap your calendar? See the Delivery Dates feature or start a free 14-day trial.