SMART Preorder vs REZ Preorder, Back In Stock

Updated November 2, 2026 · SMART Preorder & Back in stock (E-TRADE PARTNER)

SMART Preorder is free and charges deposit balances automatically, with retries. REZ Preorder, Back In Stock, by REZ Commerce, has a Free plan with 20 pre-orders and 30 back in stock emails a month and paid plans from $4.99/mo to $48.99/mo; its help center says you collect the remaining balance by hand in Shopify admin. REZ also sells back-in-stock-only plans and includes onboarding with its founder on the Free plan.

REZ prices by volume and counts every pre-order item, so one order with two pre-order items uses two. SMART has no volume pricing. The rest of the gap is in what happens after checkout: charging the balance and holding the order until stock arrives.

Quick comparison

Sources, checked November 2, 2026: REZ on the Shopify App Store and REZ pricing. Prices are USD list prices as shown on those pages, and features are described the way the vendor describes them. Trademarks belong to their owners. SMART Preorder is not affiliated with REZ. Spot something out of date? Email support@etradepartner.io.

When SMART Preorder fits better

• You take deposits and don't want to charge each balance yourself. REZ's partial payments guide has you collect every remaining balance from the Shopify order page. SMART charges it on the schedule you set and retries a declined card (how balance charges work).
• You want pre-order orders held without building automation. In SMART, choosing On hold under the campaign's fulfillment settings is enough (fulfillment holds and 3PLs). REZ's hold guide uses a Flow workflow you set up.
• You want deposits on a store that isn't on a paid plan. REZ lists full/partial payment and deposits among its Basic features ($4.99/mo); SMART includes them, along with pre-order discounts (deposits).
• You also want to hide, rename or reorder payment methods at checkout from the same app (payment rules).

When REZ fits better

• Your store is new and one restock has to reach a big waitlist. SMART allows 25 back in stock emails a day for stores under 14 days old and 100 a day for most stores with fewer than 10 paid orders in the last 90 days. REZ's back-in-stock-only plans count emails by the month instead: 2,500 on Basic ($8.99/mo), up to 15,000 on Scale ($28.99/mo).
• You'd like a guided start. REZ's listing includes onboarding with the founder on the Free plan.
• You plan stock from demand data. REZ's listing describes built-in analytics that track demand, forecast inventory and measure revenue.
• You want your own HTML emails right away. REZ lists custom email domain and HTML email on Basic ($4.99/mo). SMART's email Code tab turns on once a store has 10 paid orders in the last 90 days, or right away on Shopify Plus.

Back in stock in SMART

Each signup gets one automatic email when the variant is back, plus an optional reminder a day later if the shopper hasn't bought. You can set a Minimum quantity before anyone is emailed, count stock only at the locations you choose for each market, and send or resend by hand from the Signups tab. Limits by store size are listed in plans and limits.