Shopify "Notify Me When in Stock": Step-by-Step Setup & Copy

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You're losing 15-30% of potential sales every time a product goes out of stock on Shopify. Customers land on the page, see "Out of Stock," and bounce—most never come back. A "Notify Me When in Stock" system flips that equation: capture their email, automatically alert them when inventory returns, and convert them into buyers.

According to Shopify's own data, stores using back-in-stock alerts recover an average of 18% of would-be lost sales. That's an extra $18K per year for a store doing $100K in revenue—for maybe $30/month in app costs and 30 minutes of setup time.

In this guide, I'll walk you through exactly how to set up "Notify Me When in Stock" on Shopify: choosing the right app, installing it via OAuth, customizing the button and email templates, testing on mobile, and troubleshooting common issues. You'll be live and recovering sales by the end of this article. This is part of our complete Back-in-Stock Alert Apps comparison and Stockout Prevention system.

Choosing the Right Shopify Back-in-Stock App

Shopify's App Store has 50+ back-in-stock apps. Most are similar in functionality, but a few stand out. Here's the quick decision framework:

Top 3 Recommendations for Shopify

1. Back in Stock by Back in Stock ($19-79/mo)

• ✅ Fastest inventory sync (1-5 minutes)
• ✅ Best analytics (recovered revenue tracking)
• ✅ Customer segmentation (VIP-first notifications)
• ✅ A/B testing built-in
• ❌ SMS costs extra (Twilio integration)

Best for: Stores doing $50K+/month who want reliability and detailed reporting. Worth the cost if you have >50 stockouts per month.

2. Swym Wishlist+ (Free-$49/mo)

• ✅ Free tier (50 notifications/month)
• ✅ Combines wishlist + back-in-stock
• ✅ Push notifications included
• ❌ Slower sync (10-15 minutes)
• ❌ Limited segmentation on free tier

Best for: Budget-conscious stores or those testing back-in-stock for the first time. Free tier is generous enough to prove ROI before upgrading.

3. Klaviyo (built-in) ($20+/mo, scales with contacts)

• ✅ Powerful segmentation using full customer data
• ✅ Multi-channel (email + SMS + push if you have app)
• ✅ Best attribution and reporting
• ❌ Only worth it if you already use Klaviyo for email
• ❌ Steeper learning curve

Best for: Existing Klaviyo customers. Don't install Klaviyo just for back-in-stock—the other apps are easier and cheaper for this single use case.

For a complete comparison of all 7 top apps with pros/cons and pricing, see our detailed guide: Best Back-in-Stock Alert Apps.

What to Check Before Installing

Before you commit to an app, verify these in the App Store listing:

• Recent reviews: Read reviews from last 30 days (not 2 years ago). Check for sync speed complaints or support issues.
• App rating: Minimum 4.5 stars with 100+ reviews. Lower = red flag.
• Last updated: App should be updated within last 3 months. Abandoned apps break with Shopify updates.
• Free trial: Must have at least 7-day trial. Never pay upfront without testing.
• Pricing transparency: Avoid apps with hidden fees or unclear notification limits.

Installing the App (OAuth & Permissions)

Step-by-Step Installation

Step 1: Find the App in Shopify App Store

1. Log into your Shopify admin panel
2. Click "Apps" in the left sidebar
3. Click "Shopify App Store" button
4. Search for your chosen app (e.g., "Back in Stock")
5. Click the app from search results

Step 2: Review App Details

Before clicking "Add app," review:

• Pricing: What tier do you need? (Usually based on notification volume)
• Free trial: How many days? (7-14 typical)
• Reviews: Scroll through recent feedback
• Support: What channels? (Email, live chat, phone)

Step 3: Install via OAuth

1. Click "Add app" button
2. Shopify OAuth permission screen appears
3. Review requested permissions (typically includes):
   • Read products: To detect which items are out of stock
   • Read inventory: To monitor stock levels and trigger alerts
   • Read customers: To send notifications to the right people
   • Write metafields: To store waitlist data
   • Read orders: To track attribution (who bought after alert)
4. Click "Install app"
5. Wait 5-10 seconds for connection
6. You're redirected to the app's onboarding dashboard

Step 4: Initial Configuration

Most apps have a 3-5 step onboarding wizard:

1. Welcome screen: Click "Get Started" or "Begin Setup"
2. Store sync: App scans your products (takes 1-2 minutes)
3. Email sender: Configure "From" email address (use your domain email, e.g., This email address is being protected from spambots. You need JavaScript enabled to view it.)
4. Basic settings: Choose button placement, default templates
5. Test mode toggle: Some apps have test mode (use it!)

Don't worry about perfecting settings now—you'll refine them in the next steps.

Understanding App Permissions

Why does the app need these permissions?

• Read products + inventory: To detect when products go out of stock (quantity = 0) and when they're back (quantity > 0). Without this, the app can't function.
• Read customers: To send personalized emails using customer name and email address. For logged-in customers, this pre-fills the waitlist signup form.
• Write metafields: To store waitlist data attached to products (who signed up for which item). This keeps data organized within Shopify's structure.
• Read orders: To track attribution—did someone who received an alert actually purchase? This powers the "recovered revenue" metrics.

All of these are standard and necessary. If an app requests more permissions (like "write orders" or "read payment methods"), that's a red flag—it doesn't need those.

Setting Up the "Notify Me" Button

Button Placement Options

Most apps offer 3 placement options:

Option 1: Replace "Add to Cart" (Recommended)

• When product is out of stock, "Add to Cart" button disappears and "Notify Me" appears in its place
• Pros: Most obvious to customers, highest signup rate
• Cons: None (this is the standard pattern customers expect)

Option 2: Below "Add to Cart"

• "Notify Me" button appears below the (disabled) "Add to Cart" button
• Pros: Doesn't require JavaScript to hide/show elements
• Cons: Less prominent, lower signup rate (~30% fewer signups than replacement method)

Option 3: Custom Position (Developer Required)

• Manually place button in specific theme location using Liquid code or CSS selectors
• Pros: Full control over design and placement
• Cons: Requires theme editing, breaks if theme updates

Recommendation: Start with Option 1 (replace "Add to Cart"). It works out of the box and converts best. Only use custom placement if you have specific brand guidelines or a heavily customized theme.

Customizing Button Appearance

Most apps provide visual customization options:

Button Text

Test these variations:

• "Notify Me When Available" (clear, 10-15% conversion)
• "Get Restock Alert" (shorter, 12-18% conversion)
• "Email Me When Back" (direct, 8-12% conversion)
• "Join Waitlist" (social proof angle, 15-20% conversion)

Data from Shopify Partners suggests "Join Waitlist" performs best because it implies exclusivity and community.

Button Color & Style

Match your brand's primary CTA color:

• If your "Add to Cart" is green, make "Notify Me" green
• If your "Add to Cart" is black, match that
• Consistency = trust. Don't make it a wildly different color.

Most apps let you set:

• Background color
• Text color
• Border radius (rounded vs. square)
• Button size (match your theme's button sizing)
• Icon (email icon, bell, or none)

Mobile Optimization

Critical: Test button on mobile (60%+ of traffic). Ensure:

• Button is at least 44px tall (iOS minimum touch target)
• Text doesn't wrap awkwardly
• Button doesn't overflow product container
• Popup form is mobile-friendly (not desktop-sized)

Signup Form Configuration

What information do you collect when someone clicks "Notify Me"?

Option 1: Email Only (Recommended)

• Lowest friction = highest signup rate
• For logged-in Shopify customers, email is pre-filled (one-click signup)
• For guest visitors, they type email address

Option 2: Email + Phone Number

• Enables SMS alerts (higher conversion than email)
• Reduces signup rate by ~30% (more friction)
• Only worth it for high-value products (>$100)

Option 3: Email + Name

• Enables email personalization ("Hi Sarah,")
• Reduces signup rate by ~15%
• Marginal benefit (you can personalize with email alone if they're a customer)

Recommendation: Start with email-only. After 30 days, A/B test adding phone number for your top 20% revenue-driving SKUs. Track signup rate vs. SMS conversion lift to see if the tradeoff is worth it.

Variant-Level vs Product-Level Signup

If you sell products with variants (size, color), configure this correctly:

Variant-specific signups (Recommended)

• Customer signs up for "Blue Shirt - Size M"
• Alert only sends when that specific variant restocks
• More relevant = higher conversion
• Requires app that supports variant tracking (most do)

Product-level signups

• Customer signs up for "Blue Shirt" (any size)
• Alert sends when any variant restocks
• Less relevant but simpler to implement
• Use this only if you have

Check your app's settings—most default to variant-level, which is what you want.

Configuring Email Templates & Copy

Email Template Anatomy

Most apps provide default templates. Here's how to customize each element:

From Name & Email

• From Name: Your store name (e.g., "Jane's Boutique")
• From Email: Use your domain email (This email address is being protected from spambots. You need JavaScript enabled to view it.) NOT a generic Gmail
• Why: Improves deliverability and brand recognition

Subject Line (Test These)

High-converting variations:

• "[Product Name] is back in stock" (straightforward, 12-18% open rate)
• "Good news! Your waitlist item is available" (personal, 15-22% open rate)
• "Hurry—[Product Name] limited restock" (urgency, 18-25% open rate for limited stock)
• "You're off the waitlist 🎉" (celebratory, 10-15% open rate)

Avoid:

• Generic: "Product available" (too vague)
• Spammy: "BUY NOW!!!!!" (triggers spam filters)
• False urgency: "Only 2 left" when you have 500 units

Preheader Text

The ~100 characters that appear after subject line in inbox preview:

• "Shop now before it sells out again"
• "Limited quantities available—don't miss out"
• "Your wait is over. Get yours today."

Don't leave this blank—it defaults to "View this email in your browser" which wastes prime real estate.

Email Body Structure

Keep it simple. This template converts at 15-20%:

For Limited Restocks (scarcity angle):

CTA Button Best Practices

• Text: "Shop Now" or "Get Yours" (test both)
• Color: Match your store's primary button color
• Size: Large and prominent (40-50px height minimum)
• Link: Direct to product page (not homepage)
• UTM parameters: Include ?utm_source=back_in_stock&utm_medium=email for tracking

Timing & Send Strategy

When to Send

• Immediately: As soon as inventory updates (1-10 minutes) - best for fast-moving products
• Batched (30-minute delay): Groups multiple restocks into one email if customer is on multiple waitlists
• Scheduled: Send at optimal time (9am local time) - only use for large restocks that won't sell out quickly

Recommendation: Immediate send for 90% of products. Batching makes sense only if customers frequently sign up for 3+ products and you're restocking in bulk.

Segmentation (If App Supports It)

Send to VIP customers first:

1. Hour 0: Notify VIPs (Shopify customer tag "VIP" or >$500 lifetime spend)
2. Hour 24: Notify remaining waitlist if inventory still available

This rewards loyalty and reduces re-stockout risk (VIPs convert at 2-3x higher rates, so you can gauge demand before broadcasting to everyone).

SMS Template (If Enabled)

Keep under 160 characters:

• "[Product Name] is back! Limited stock: [Short Link] -[Store Name]"
• "You're off the waitlist. [Product] restocked: [Link]"
• "Hurry! [Product] just arrived: [Link] -[Store]"

SMS converts 2x better than email (20-35% vs. 10-20%) but costs $0.01-0.03 per message. Use SMS for:

• High-value products (>$50)
• VIP customers
• Products that historically sell out in