Reservation Limits and Security
Cart Reserve includes safeguards to prevent abuse and excessive inventory locking.
These limits ensure fair access to inventory during high-demand periods.
Reservation Limits
- Maximum of 20 renewals per session
- Session lifetime capped at 24 hours
- Free uses a fixed 10-minute timeout; paid plans can configure 5 to 60 minutes
- Maximum quantity per variant enforced based on available inventory
Plan-Based Limits
Some features are gated by your subscription plan.
| Feature | Free | Starter | Pro | Max |
|---|---|---|---|---|
| Reservations / month | Unlimited | Unlimited | Unlimited | Unlimited |
| Concurrent active holds | 25 | 100 | 500 | 2,500 |
| Protected products | 3 | 100 | 500 | Unlimited |
| High-traffic behavior | Capacity protection | Fair queue | Advanced fair queue | Advanced fair queue |
| Session-detail retention | 1 day | 1 day | 30 days | 90 days |
| Dashboard history | 1 day | 7 days | 30 days | 90 days |
| IP and country blocking | — | — | — | Unlimited |
| Global quantity limit | — | — | — | Available |
"Concurrent reservations" is the number of carts that can hold real inventory at the same time (active holds within their timer window). It is the main plan limit — monthly reservation volume itself is unlimited. When a store hits its concurrency limit during a rush, additional shoppers wait in a fair queue and are let in as holds free; no reservation is rejected.
AI Insight quotas reset on a monthly cycle. Pro reports can analyze up to 30 days; Max reports can analyze up to 90 days.
Abuse Prevention
Cart Reserve monitors reservation behavior to prevent:
- Excessive inventory locking by a single session
- Automated cart abuse (bot detection)
- Invalid reservation creation patterns
- Checkout attempts that skip the reservation system
Checkout Protection for Reserved Products
Reserved products are protected at checkout, even if a shopper tries to work around the reservation system.
If someone reaches checkout with a reserved product but without a valid reservation — for example by disabling the app in their browser, using an ad blocker, or editing the cart directly — Cart Reserve stops the checkout and asks them to reserve the item first.
This closes a loophole where a determined shopper could otherwise grab high-demand stock without holding a reservation, which is especially important during drops and limited releases.
Products that are not set up for reservations are never affected — shoppers can always buy them normally, including through express and one-click checkout.
Checkout enforcement only applies to variants Cart Reserve can actually hold: those with tracked, finite stock. Variants set to "Continue selling when out of stock" (which Shopify allows to oversell) and untracked, made-to-order variants are never blocked at checkout — even on an enabled product — because there is no limited stock to protect. See Inventory and Conflicts for the full breakdown.
Why Limits Exist
Without limits, a single session could lock large portions of inventory without completing checkout.
These safeguards ensure predictable behavior and protect inventory availability for all customers.