A back in stock email in WooCommerce is an automatic message sent to shoppers who asked to be told when a sold-out product returns. For a store with one list and limited hours, it is usually the better first automation: the people on it already chose a product, gave an email, and are waiting to pay.
Which WooCommerce automation should a small store build first?
If your bestsellers sell out even a few times a year, build back-in-stock notifications first. They take an afternoon, need one email instead of a three-part series, need no discount, and reach people who already picked a product. Cart recovery earns more on high-traffic stores with steady stock, and most small stores don't look like that.
The question usually reaches us in a familiar shape. A store owner has one email list of about 30,000 addresses, roughly 200 visitors a day, and maybe five spare hours a week to spend on marketing. She has read that abandoned cart emails are the top-earning automation in ecommerce. She has also noticed that her three best products sell out after every production run, and customers keep emailing to ask when they'll be back.
She can build one automation this month. Most guides tell her to start with cart recovery, and for a store doing thousands of sessions a day that order makes sense. At 200 visitors a day with frequent stockouts, the numbers point the other way.
What is a back-in-stock email in WooCommerce?
A back-in-stock email is triggered when a product's stock goes from zero to available. A "Notify me" form replaces the add-to-cart button on sold-out products or variants, the shopper leaves an email, and when you restock, the plugin emails everyone waiting on that item with a link straight to the product.
WooCommerce stores usually add this with a plugin. The common choices are Back In Stock Notifier for WooCommerce (free on WordPress.org), YITH WooCommerce Waitlist, and the Back In Stock Notifications extension sold on WooCommerce.com. All three handle variable products, which matters if your stockouts are a specific size or color and the rest of the product is still in stock.
The difference from cart recovery is intent. Someone who abandons a cart might have been checking shipping costs, comparing you with another store, or browsing on a phone during a meeting. Someone who joins a waitlist told you the exact product they want, gave you an email for that reason alone, and is now waiting on you.
Back-in-stock vs abandoned cart revenue at 200 visitors a day
For our example store, back-in-stock notifications earn roughly $1,100 a month and cart recovery about $400. Treat both as rough: every input below is an assumption you should swap for your own analytics. The gap comes from reach. Cart recovery can only email abandoners whose address you captured, and that is a small slice.
Start with traffic. 200 visitors a day is about 6,000 sessions a month. The average order is $58.
For back-in-stock, assume 20% of sessions land on a product or variant that is sold out. That's 1,200 sessions. If 8% of those shoppers join the waitlist, you collect 96 signups a month. If 20% of signups buy when the item returns, that's about 19 orders, or $1,100.
For cart recovery, assume 6% of sessions add something to the cart, which gives 360 carts. According to Baymard Institute's average across 49 studies, 70.19% of online shopping carts are abandoned (2024), so about 252 carts are left behind. Here's the catch: you can only email the shoppers who entered an address at checkout or were logged in. Call that 35%, or 88 people. A three-email series recovering 8% of them brings back 7 orders, about $400.
| Metric (monthly) | Back-in-stock notifications | Abandoned cart recovery |
|---|---|---|
| Who gets the email | Shoppers who asked about one product | Abandoners whose email you captured |
| People reachable | 96 waitlist signups | 88 of 252 abandoners |
| Emails sent | 96 (one each) | 264 (three-email series) |
| Assumed conversion | 20% | 8% |
| Orders | About 19 | About 7 |
| Revenue at $58 AOV | About $1,100 | About $400 |
| Emails sent per order | About 5 | About 38 |
The last row deserves attention. Back-in-stock sends far fewer messages for every sale, which means fewer chances for someone to hit "report spam." That ratio matters more than it looks once you get to the deliverability section below.
Your 30,000-address list adds something on top. Waitlist signups are new, consented addresses joining the list at around 96 a month in this model. And when a bestseller returns, you can send a separate "back by demand" campaign to past buyers of that category, which is a bigger lever than the notification itself, and also a much bigger send.
How much setup time does each automation take?
Back-in-stock takes about half a day for most stores: install a plugin, style the form, write one email, test a restock. Cart recovery takes one to two days done properly, because you need early email capture at checkout, three emails with timing decisions, and a call on whether to offer a discount.
These are our estimates from setting both up on WooCommerce stores, and your theme and checkout plugins will shift them.
| Task | Back-in-stock | Cart recovery |
|---|---|---|
| Emails to write | 1 | 3, with send timing for each |
| Discount decision | Usually none needed | Often expected by the third email |
| Checkout changes | None | Capture email before payment step |
| Typical setup time | 2-4 hours | 1-2 days |
| Ongoing tuning | Check signups after each restock | Test timing, subject lines, discount levels |
The discount line has a cost beyond setup. Once shoppers learn that leaving a cart triggers a 10% code, some of them leave carts on purpose. Waitlist customers don't need a discount to buy something they asked for, so every recovered order keeps its full margin.
Why do restock emails from a shared host land in spam?
Restock emails sent by WordPress on a shared host usually leave through the server's own mail function, from an IP address shared with hundreds of other sites. That mail is rarely signed with DKIM for your domain, often fails SPF, and inherits whatever reputation your server neighbors earned. Gmail and Outlook treat it accordingly.
The rules got stricter in 2024. According to Google's email sender guidelines, from February 2024 every sender to Gmail must authenticate with SPF or DKIM, and anyone sending more than 5,000 messages a day to Gmail addresses must have SPF, DKIM and DMARC in place, offer one-click unsubscribe, and keep the spam complaint rate below 0.3%. Yahoo announced matching requirements at the same time.
A waitlist of 96 people won't trip the bulk threshold. Your 30,000-address restock announcement can. On a typical consumer list a large share of addresses are Gmail, so one campaign day can cross 5,000. If that blast goes out through the same unauthenticated path as your order receipts, a complaint spike can drag your order confirmations into spam with it.
There's also the volume ceiling. Many shared hosting plans cap outbound mail at a few hundred messages an hour, and messages over the cap get queued, delayed or dropped. A restock that should reach everyone in ten minutes trickles out over a day, and the people at the back of the queue find the product sold out again.
We covered why a host's included mailboxes aren't a business email plan in our post on using your host's email servers, and the SMTP side in our WordPress email deliverability guide. Restock notifications are requested, one-to-one messages, so they belong on the transactional stream with your receipts. Your newsletter and "back by demand" campaigns go on a separate path, which is the setup we laid out in keeping transactional email off your marketing subdomain.
Why do WooCommerce back-in-stock emails send late or not at all?
Most notify plugins don't send every email the moment you restock. They queue the sends in batches through WP-Cron or WooCommerce's Action Scheduler. WP-Cron only runs when a visitor loads a page that reaches PHP, so on a quiet store, or one where full-page caching serves most visits, queued emails can wait hours.
The WordPress developer documentation states this directly: WP-Cron checks for due tasks on page load, not on a clock. At 200 visitors a day, traffic is thin overnight and on weekends. Restock a product at 9 p.m. after the shipment arrives, and the first batch may not go out until someone browses the next morning. Caching makes it worse, because cached pages can be served without touching WordPress at all.
The other failure is a store with DISABLE_WP_CRON set to true in wp-config.php and no server cron put in its place. Someone disabled WP-Cron for performance, often correctly, and nobody added the replacement. Scheduled actions then pile up forever.
You can check in two minutes. Go to WooCommerce, then Status, then Scheduled Actions, and filter by "Past-due." A handful is normal. Dozens or hundreds of past-due actions mean your cron isn't firing, and your restock emails, along with subscription renewals and scheduled sales, are waiting on it.
How to set up back-in-stock emails in WooCommerce
Setting up back-in-stock emails takes seven steps: pick a plugin, show the form on sold-out variants, write one email, authenticate your sending, confirm cron runs, test with real inboxes, and track the revenue. Steps four and five are where most stores lose the sale without noticing.
- Choose a plugin that supports variations. Back In Stock Notifier for WooCommerce is a reasonable free start; the paid options add better reporting.
- Show the notify form on sold-out products and on individual sold-out variants. A shopper who wants size M shouldn't have to sign up for the whole product.
- Write one email with the product photo, current price, and a link that goes to the product page with the variant preselected. If stock is limited, say how many you have. That number does more than a discount.
- Route WordPress mail through an authenticated transactional service, then publish SPF, DKIM and DMARC records for your sending domain.
- Confirm cron runs on a real server schedule, then check Scheduled Actions again after your first restock.
- Test it end to end: mark a product out of stock, sign up with a Gmail and an Outlook address, restock, and time how long the emails take to arrive and which folder they land in.
- Add UTM tags to the email link and watch WooCommerce's order attribution report, the same approach we use for measuring when a WooCommerce blog turns into store revenue.
When a popular item comes back, it helps to say so beyond the waitlist. A one-line header announcement like "Back by demand: the linen apron is restocked" is the kind of text swap our AI edits included with hosting can make from a chat, with a preview first and undo for 30 days.
When should cart recovery come first?
Build cart recovery first if you rarely run out of stock, if your traffic is well above a few hundred visitors a day, or if your checkout already captures email early. Print-on-demand and dropship stores fit this pattern: almost nothing sells out, so a waitlist has nobody to collect.
High average order values also tilt the math. At $400 an order, recovering even three carts a month can beat a modest waitlist, and the discount question becomes easier because a small percentage still leaves good margin. Our abandoned cart recovery guide covers SMS timing, retargeting and the series structure that works without adding another exit-intent popup.
Before building either, check checkout speed. A slow checkout produces abandoned carts that no email will win back, and that is a hosting problem first, as we explained in why WooCommerce stores need managed hosting instead of shared. Fixing it raises the ceiling for both automations.
What managed hosting changes for WooCommerce restock emails
Managed hosting fixes the two infrastructure problems that break restock emails: unauthenticated mail and a cron that waits for traffic. On TopSyde, WordPress cron runs from a real server schedule, store mail goes out through authenticated transactional sending, and we monitor the site 24/7 so a stalled queue gets noticed.
Our plans start at $89/mo per site, and the pricing page lists what's included at each tier. If you want the technical detail on how cron, caching and mail are configured, the stack page covers it. Solo store owners usually start with our hosting for individuals, and support responds in under 2 hours during business hours when something needs a human.
Every plan carries a 30-day money-back guarantee, and we handle the migration. Move the store, build the waitlist in an afternoon, and run your first restock on infrastructure that sends the email when the stock comes back.
Frequently Asked Questions
Are back-in-stock emails transactional or marketing email?
A notification sent only because a customer asked about one product is generally treated as transactional, since its main purpose is the information they requested. Once you add unrelated promotions, it starts to look like marketing. Include an unsubscribe link either way, and check GDPR or CASL requirements with counsel if you sell into the EU or Canada.
Should I add a discount code to back-in-stock emails?
Usually not. Waitlist shoppers already chose the product and asked to hear about it, so a discount mostly gives away margin on sales you'd have made anyway. A clear note about limited quantity tends to do the persuading.
How do I know if my restock emails are going to spam?
Send a test restock to Gmail and Outlook addresses you control and check which folder each lands in. Set up Google Postmaster Tools for your sending domain to see spam rates and authentication results. Also check WooCommerce's Scheduled Actions for past-due tasks, since emails that never leave look the same as emails filtered to spam.
Is 200 visitors a day enough traffic for back-in-stock emails to be worth it?
It depends on how often you sell out. A store with regular stockouts on its bestsellers can collect dozens of signups a month at that traffic level, and setup takes only a few hours. A store that never runs out will collect almost nobody, and cart recovery is the better first project.
Content & SEO Strategist
7+ years SEO & content strategy, Google Analytics certified
Elena drives content strategy and SEO at TopSyde, helping clients maximize organic visibility and AI search presence. She combines technical WordPress knowledge with data-driven content optimization.
