When stock runs out, there are two moves: tell customers when it's back, or take the order now.

Neither is fully covered by Shopify natively — but for completely different reasons. Back-in-stock notifications simply don't exist in the platform. Pre-orders, by contrast, reach into Shopify's payment infrastructure, and the documentation lists specific payment methods and sales channels that fall outside them.

The most persistent misconception about pre-orders is that they require Shopify Plus. Reading the official documentation, no such requirement exists. What you do lose is Shop Pay, Apple Pay, and Google Pay — which may matter considerably more to revenue.

Below: the native boundary established from the Shopify Help Center and shopify.dev, then five back-in-stock apps and three pre-order apps normalized on how they meter. Researched August 31, 2026.

The short version

Back-in-stock notifications don't exist natively. They appear neither in the customer notifications list nor in the Liquid variable reference for notification templates. An app is mandatory.

Pre-orders do not require Shopify Plus. Neither shopify.dev's purchase options documentation nor its limitations section mentions Plus as a requirement. The actual gate is the payment gateway.

What you lose instead: Shop Pay, Apple Pay, and Google Pay cannot buy pre-order items. The Help Center states this outright. Stores where accelerated checkout carries a large share of revenue should model that impact first.

Shopify POS, draft orders, and B2B are also out of scope. shopify.dev additionally lists Buy X get Y discounts as unsupported, local payment methods as unavailable, and stores on checkout.liquid custom checkout as ineligible.

The first-party Shopify Subscriptions app cannot do pre-orders. It covers weekly, monthly, and yearly recurring subscriptions only, and the Help Center states plainly that using pre-orders requires installing a pre-order app from the App Store.

Pre-order apps meter on four different axes: monthly order count, pre-order revenue, Shopify plan tier, and notification volume. And on plan-tier apps, Plus costs more. Pre-orders don't require Plus — but being on Plus makes the app more expensive.

What native inventory settings actually cover

Shopify has a "Continue selling when out of stock" setting, applied per product or variant, that lets customers purchase after inventory reaches zero.

Three things to know.

It's only selectable when inventory tracking is on. Untracked products don't surface the option at all.

It doesn't apply to Shopify POS orders. POS instead warns staff and allows the sale to proceed — different behavior.

Multi-location display can surprise you. If the location fulfilling online orders has zero inventory, customers see "out of stock" even when other locations have stock.

And what this setting delivers is exactly one thing: selling at normal price with immediate full payment despite zero inventory. No partial payments, no deposits, no deferred balance charges, no pre-order labeling, no expected ship dates, no pre-order caps. Those all live in a different mechanism.

Pre-orders are built on the Selling Plan API

Per shopify.dev's purchase options documentation, there is no dedicated pre-order API. Pre-orders are expressed through sellingPlanGroupCreate as a combination of pricing policy, delivery policy, inventory policy, and billing policy.

The four selling plan categories are SUBSCRIPTION, PRE_ORDER, TRY_BEFORE_YOU_BUY, and OTHER.

Partial payment is expressed through the billing policy's checkout charge. You can charge a portion at checkout and collect the balance on a specific date (EXACT_TIME) or a set number of days after checkout (TIME_AFTER_CHECKOUT). Setting the checkout charge to zero produces a "$0 down" configuration where the full amount is collected later.

Shopify stores the customer's payment method as a PaymentMandate, and the balance is charged via orderCreateMandatePayment. shopify.dev is explicit that scheduling the charge timing and handling payment failures are the app's responsibility. How an app handles failed balance charges is therefore a real selection criterion, not a detail.

Not "Plus-gated" — gateway-gated

The claim that pre-orders require Shopify Plus doesn't appear anywhere on the relevant shopify.dev page or its limitations section.

The actual gate is the payment gateway. And here the two official sources disagree.

shopify.dev lists Shopify Payments, PayPal Express, Adyen on Shopify, and Stripe for some merchants. The Help Center states a narrower set: Shopify Payments or PayPal Express only.

This research could not determine which reflects current behavior. If your payment setup is neither Shopify Payments nor PayPal Express, confirm with Shopify Support before committing.

The out-of-scope list, in one place

Constraints documented across shopify.dev and the Help Center. These matter more operationally than the Plus question.

Item	Status for pre-orders
Shop Pay / Apple Pay / Google Pay	Cannot purchase pre-order items
Shopify POS	Unavailable
Draft orders	Unavailable
B2B	Unavailable
Buy X get Y discounts	Unsupported
Local payment methods	Unavailable
checkout.liquid custom checkout	Unavailable (migration to Checkout Extensibility required)
Cart permalinks	Unsupported
Order Edits API	Delete operations only
Shop Promise	Unsupported
Mixed purchase options for one product	Not possible in a single checkout

Losing Shop Pay, Apple Pay, and Google Pay is the most frequently overlooked item. On mobile-heavy stores, conversion rate on a pre-order product becomes non-comparable to its pre-launch baseline. Measuring pre-order performance without accounting for that difference produces the wrong conclusion.

The Help Center also documents cart behavior with multiple pre-order items: the earliest date applies to the whole cart, "charge on fulfillment" takes precedence over a specific date, and deposits are combined and charged together at checkout.

Five back-in-stock apps, metered differently

Values from the Shopify App Store as of August 31, 2026. Watch what number the free tier counts.

App	Developer	Free tier	Paid starts at	Rating / reviews	Built for Shopify
Notify Me! Back in Stock Alert	Notify Me!	10 alerts / 5 preorders / 50 wishlist actions	$9.90/mo	4.9 / 3,612	Yes
Preorder, Back In Stock ‑ STOQ	Artos Software	10 preorders / 30 emails per month	$10/mo	5.0 / ~3,550	Yes
Amp Back in Stock & Preorder +	HEL SG PTE LTD	10 notifications/mo	$19/mo	4.9 / 845	Yes
Swym Back in Stock Alerts	Swym Corporation	None (trial only)	$19.99/mo	4.7 / 419	No
Alert Me! Restock Alerts	Dibble Development	10 notifications/mo	$4.99/mo	4.3 / 239	No

Four observations.

First, the free tiers aren't operationally useful. Around ten notifications per month is a smoke test, not a deployment. Filtering on "has a free plan" effectively removes your ability to compare. Compare on the paid entry point instead.

Second, paid entry points span 4x. Alert Me! Restock Alerts starts at $4.99 (50 notifications); Swym starts at $19.99 (1,000 alert requests). Volumes differ too, so compare unit cost rather than headline price.

Third, Swym's "preorder" is not a pre-order. Its feature tags contain no payment-related items, and its data access scopes include no purchase options, selling plans, or payment mandate. What it offers is pre-launch demand capture — a waitlist — not a transaction. A May 14, 2026 review also notes the free plan was discontinued in favor of paid-only.

Fourth, only Notify Me! and STOQ carry Japanese interface support. Amp, Swym, and Alert Me! are English-only.

Pre-order apps meter on four different axes

Here the pricing philosophies diverge more sharply.

App	Developer	Metered on	Pricing	Rating / reviews	Built for Shopify
Preorder Now Presale Timesact	Kairock Partners SRL	Monthly orders (Flex) or Shopify plan (Fixed)	Flex from $5/mo; Fixed: Basic $23, Grow $47, Advanced $73, Plus $117	5.0 / 1,965	Yes
Preorder Wolf | Pre order now	Boss Apps	Monthly pre-order revenue	$4.99 (to $500), $19 (to $2,000), $38 (to $3,000)	4.8 / 501	Yes
Amai PreOrder Manager + Notify	Amai	Shopify plan tier	Basic $12.95, Standard $24.95, Advance $59.95, Plus $89.95	4.2 / 484	No
Notify Me! Back in Stock Alert	Notify Me!	Monthly pre-orders	$9.90 (500) to $39.90 (1,500), overage $0.15–0.20/order	4.9 / 3,612	Yes
Preorder, Back In Stock ‑ STOQ	Artos Software	Monthly pre-orders + notifications	$10 (100 + 1,000) to $69 (unlimited)	5.0 / ~3,550	Yes

Plan-tier pricing deserves the most attention.

Amai PreOrder Manager + Notify prices on the merchant's Shopify plan rather than usage. Basic is $12.95/month; Plus is $89.95/month. Same feature set, roughly 7x the price.

Preorder Now Presale Timesact's CORE Fixed plans work the same way: $23/month on Basic, $117/month on Plus. But Timesact also offers a Flex line starting at $5/month, metered in increments of 10 additional orders with $0.20-per-order overage. A Plus store with modest pre-order volume changes its cost dramatically just by choosing Flex over Fixed.

Preorder Wolf's revenue-based metering was the only one of its kind in this research. $4.99/month covers $500 in monthly pre-order revenue, $19 covers $2,000, $38 covers $3,000. High-AOV stores hit those ceilings far faster than order-count pricing would suggest; low-price, high-volume stores come out ahead. Its free plan is restricted to test, development, and partner stores — not production.

Apps that vanished or got renamed

Three items surfaced that commonly appear in comparison articles but no longer match reality. Worth knowing when you read older roundups.

PreOrder Now WOD (developer: Website on Demand Studio, LLC) is not currently distributed on the App Store as of August 31, 2026. Its page displays "This app is not currently available on the Shopify App Store." No pricing, rating, or feature data is available, so it cannot be evaluated as a current option.

The app at apps.shopify.com/back-in-stock is no longer "Back in Stock ‑ Restock Alerts." It's now "Amp Back in Stock & Preorder +," from HEL SG PTE LTD under the Amp brand.

"Notify! Back in Stock|PreOrder" has been renamed "Notify Me! Back in Stock Alert."

App names and URL handles change. When reading comparisons, open the actual App Store page and verify the current name and availability.

Choosing by situation

You only need to notify customers when stock returns

A back-in-stock app is required; nothing native exists. STOQ and Notify Me! lead on features and language coverage. If cost dominates, Alert Me! Restock Alerts runs $4.99/month for 50 notifications.

You just want to keep selling at zero inventory

No app needed. Toggle "Continue selling when out of stock" on the product or variant. Confirm three things: inventory tracking is on, POS is unaffected, and you understand multi-location display behavior.

You want to take a deposit and charge the balance later

A pre-order app is required. Plus is not — but the gateway requirement applies, and Shop Pay, Apple Pay, and Google Pay stop working for those items. Partial payment support was confirmed for Notify Me! (Kickstart and above, percentage or fixed), STOQ, Timesact, and Amai. Swym and Alert Me! do not offer it.

You're on Shopify Plus

Avoiding plan-tier pricing (Amai, Timesact CORE Fixed) alone changes your monthly cost substantially. If you want Timesact, look at the Flex line. If pre-order volume is modest, order-count pricing from Notify Me! or STOQ may come out cheaper still.

You need both pre-orders and back-in-stock alerts

Notify Me! and STOQ each cover both in a single app. Both carry Built for Shopify badges and support Checkout extensions. That makes them the first place to look when minimizing app count.

You want to take pre-orders in-store on POS

Pre-orders don't work on POS. That's a platform constraint, not something an app can route around.

Pre-install checklist

• Do you know what share of revenue comes through Shop Pay, Apple Pay, and Google Pay — all unavailable on pre-order items
• Is your gateway Shopify Payments or PayPal Express; if not, have you confirmed with Support
• Are you still on checkout.liquid custom checkout (migration required if so)
• Do your requirements include POS, B2B, or draft order pre-orders
• Which axis does the app meter on: orders, revenue, Shopify plan, or notifications
• If you're on Plus, have you avoided plan-tier pricing
• Past the free tier, is it metered overage or a forced plan upgrade, and at what unit rate
• How the app handles failed balance charges (scheduling is documented as the app's responsibility)
• Interface language and support language, checked separately
• Whether every app in your shortlist is still distributed on the App Store

In short

Four steps, in order.

1. Separate out what native settings already cover. If "sell at normal price with immediate full payment despite zero stock" is the whole requirement, no app is needed. The app conversation starts at deposits and deferred charges.
2. Judge on payment methods and sales channels, not on Plus. Pre-orders don't need Plus. What breaks is Shop Pay, Apple Pay, Google Pay, plus POS, B2B, and draft orders.
3. Identify the metering axis first. Orders, revenue, plan tier, or notifications. High-AOV catalogs hit Preorder Wolf's revenue ceilings early. Plus stores change their bill just by avoiding plan-tier pricing.
4. App names and URLs change. When working from an older comparison, open the App Store page and verify current naming and availability — some listings are gone.

Pricing, ratings, and features reflect what the Shopify App Store, Shopify Help Center, and shopify.dev showed on August 31, 2026. The payment gateway requirement is documented inconsistently between shopify.dev and the Help Center, so confirm with official support before committing.