Which plan do I need for delivery capacity limits?

Capacity limits are part of the Advanced plan delivery suite, with a 14-day free trial and no Shopify Plus requirement.

Can two customers book the last slot at the same time?

In a narrow case, yes — and we'd rather say so. Checkout validation reads a snapshot of what's already booked and can't hold a lock the way Shopify does for stock. Two shoppers checking out within the same second, for the same date, with one place left, can both get through. It needs near-simultaneous checkouts on a date already down to its last slot, so it's uncommon — but it isn't impossible, and no app on this platform can promise otherwise.

What happens to capacity when an order is cancelled?

The slot is released automatically and becomes bookable again, so a cancellation frees the place for another customer.

Delivery capacity limits

3 min read · Facts checked October 12, 2026

Capacity limits keep a delivery date from taking more orders than you can fulfill. They're the delivery side of the same idea as OrderRules' order caps.

Per-date and per-slot caps. Limit how many orders each delivery date — and each time slot within it — can take. The per-date cap is one store-wide number, Maximum orders per delivery date (Delivery Dates → More options → Delivery date behavior). Slot caps are the Cap/day on each window in Time slot templates.
Blocked at checkout. Once a date or slot is full, checkout stops accepting it.
Auto-release on cancel. When an order is cancelled, its slot is released and becomes bookable again.
Places left on slots. A capped slot shows how many places remain, and a full one shows as Full.

Caps are enforced at checkout by the OrderRules Shopify Function, so express and Shop Pay checkouts are validated the same way as the standard one. POS orders, order edits and orders created through the API aren't validated.

What the cap does

Behaviour	What it means
Per-date and per-slot caps	Limit orders for a whole day (one store-wide number), and inside each window
Blocked at checkout	A full date or slot is rejected at checkout, not just hidden
Auto-release on cancel	A cancelled order frees its slot for someone else
Enforced at checkout	The Shopify Function also covers express and Shop Pay checkouts
Places left	Capped slots show how many places remain

The one limit worth knowing

Checkout validation reads a snapshot of what's booked; it can't reserve a place the way Shopify reserves stock. So two customers checking out within roughly the same second, for the same date, with a single slot left, can both succeed.

In practice that needs near-simultaneous checkouts on a date already down to its last place, so it's rare. But it is a platform limitation rather than something a future release removes — and an app that tells you otherwise is promising something Shopify doesn't offer.

Time slots · Availability rules · Blackout dates & holidays
Capacity calculator: per-slot and per-date caps from your staff and drivers
Limits by delivery date — cap a product's daily output against the delivery date, set on the product rather than the availability rule

Time Slots Limits by Delivery Date

Delivery capacity limits

What the cap does

The one limit worth knowing

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