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Back in Stock vs REZ: 2026 comparison
Back in Stock and REZ both combine restock alerts with preorders, but they are at opposite ends of the maturity curve. Back in Stock created the category in 2011 and has been used by 112,000+ merchants; REZ launched in May 2025, making it the newest app in this comparison by a wide margin. Back in Stock also delivers alerts via email, SMS, and web push — REZ's listing covers email only — and its flat plans carry no automatic overage fees, where REZ bills per preorder and per email above plan caps.
Full feature comparison
| Back in StockRecommended | REZCompetitor | |
|---|---|---|
| In market since | 2011 | 2025 |
| Free plan | Yes | Yes |
| Pricing model | Flat + opt-in top-ups | Usage-based overages |
| Entry paid price | $19/mo | $4.99/mo |
| Top-tier price | $99/mo (unlimited) | $28.99/mo |
| Automatic overage fees | None — opt-in top-ups | (above plan caps) |
| Free trial | 14 days | 7 days |
| Preorders | Yes | Yes |
| Notification channels | Email, SMS, Push | |
| Wishlist module | Coming soon | No |
| Low-stock badges | Coming soon | — |
| Multi-language | Yes | — |
| Built for Shopify | Yes | Yes |
| Try Back in Stock for Free |
REZ figures verified against their Shopify App Store listing on July 29, 2026. Review counts and pricing change frequently — check the App Store for current details. "—" means unverified, not absent.
REZ figures verified against their Shopify App Store listing on July 29, 2026. Review counts and pricing change frequently — check the App Store for current details. "—" means unverified, not absent.
Where Back in Stock wins
A 14-year head start
Back in Stock launched in 2011; REZ arrived in May 2025, fourteen years later. Restock alerts are revenue-critical during launches and BFCM — Back in Stock has run them at scale for some of the biggest DTC brands, including Skims, Red Bull, Alo, and Kylie Cosmetics.
Email, SMS, and web push
REZ's Shopify listing covers email notifications only. Back in Stock reaches customers on whichever channel converts — instant and scheduled email, SMS, and web push, in multiple languages, brand-matched to your store.
No automatic overage fees
REZ automatically bills $0.25 per preorder ($0.10 on Scale) and $1 per 100 emails above your plan's caps. Back in Stock's plans are flat — top-ups are an opt-in choice, never an automatic line item.
Where REZ might fit
REZ is the newest app in this comparison (launched May 2025) with low entry pricing and founder-led onboarding. If email-only restock alerts are enough and the lowest possible entry price matters most, REZ starts at $4.99/month.
Frequently Asked Questions
Is Back in Stock better than REZ?
Back in Stock is the better choice for most merchants: it has a fourteen-year track record (2011 vs May 2025), delivers alerts via email, SMS, and web push where REZ is email-only, and uses flat pricing where REZ bills automatic per-preorder and per-email overages. REZ is a low-cost newcomer with founder-led onboarding.
Does REZ send SMS or push notifications?
REZ's Shopify App Store listing covers email notifications only — no SMS or web push. Back in Stock delivers restock alerts via all three channels.
Which is cheaper — Back in Stock or REZ?
REZ's paid plans start at $4.99/month versus Back in Stock's $19/month, but REZ adds automatic overage charges per preorder and per email above plan caps. Back in Stock's flat tiers with opt-in top-ups keep costs predictable. Both offer free plans.