Drop-in SMTP relay for WooCommerce — order receipts, shipping notifications, refund confirmations, password resets, low-stock alerts, every email Woo sends. SPF + DKIM authenticated. No third-party SMTP credentials to wrangle.
Free tier: 100 routed emails / month · works with Subscriptions, Bookings, Memberships, Dokan · zero-config sender mode.
Woo orders & receipts
LiveOrder #1234 confirmed — Linen midi dress
to sarah.m@gmail.com
Order #1235 shipped — DHL 9251 8430 1144
to jenny@maplecreek.co
PDF invoice — Order #1230
to maria.r@hotmail.com
Order #1236 refund processed — $48.99
to brian.k@gmail.com
Low stock: Beech wood candle holder (3 left)
to admin@bramble-shop.com
Subscription #224 renews in 7 days
to lukas.w@gmail.com
Revenue you’re bleeding right now
A WordPress contact form that doesn’t email is annoying. A WooCommerce order confirmation that doesn’t arrive is a chargeback. Industry observations suggest first-order confirmations landing in spam are a significant driver of repeat-customer drop-off; you don’t need a precise statistic to know that’s real money walking out the door.
Customer pays, sees a thank-you page, then never gets the confirmation. Within 24 hours they either contact support thinking the order failed, or place a second order. You eat the refund, the chargeback fee, or both.
Double charge · refund · chargeback risk
Customer doesn't know their package shipped, doesn't track it, doesn't realise it's at the depot. Failed delivery, return to sender, reshipment cost, ticket volume.
Reship cost · failed delivery · support ticket
B2B customers, tax-deductible purchases and EU VAT-required transactions need a receipt that arrives. Missing receipts mean accounting follow-ups, refund threats, and in some jurisdictions a compliance problem.
Tax / VAT compliance · finance follow-ups
You issued the refund; the customer didn't get the email about it. They open a chargeback dispute anyway because they think you ignored them. You lose the dispute and pay the fee on top of the original refund.
Chargeback dispute · dispute fee · review damage
Returning customer can't log in to view past orders, re-order, or track shipments. They give up and order from a competitor. A single missing password-reset email permanently loses a repeat customer.
Account abandoned · churn
Woo sends YOU an admin email when inventory dips. If those go to spam, you miss the restock window and stock-out a top SKU during a peak buying day. Revenue lost on the SKU + every cross-sell it would have triggered.
Stock-out · missed restock window · revenue lost
First-purchase welcome email is the highest-engagement message in the whole customer lifecycle. If it doesn't arrive, the customer doesn't see your discount code, your loyalty program, your second-purchase offer — gone.
Second-purchase suppressed · LTV halved
Customer was going to skip this month but you offered an easy pause link in the renewal email. They never got it, got charged unexpectedly, refunded angrily, and cancelled the whole subscription.
Subscription cancellation · MRR lost
SecureSMTP catches all of them at the wp_mail() layer.
Every email Woo sends — every status transition, every reminder, every admin alert — goes through your SecureSMTP relay automatically once Email Delivery is on. No per-email-type configuration.
One plugin, one toggle. Your WooCommerce templates stay as they are. Only the SMTP path changes — and every email lands in the inbox instead of the spam folder.
Same plugin powers SecureSMTP forms and SMTP relay — install once, get both. Upload from /downloads/securessmtp.zip?v=1.21.0 or search “SecureSMTP” in WP admin. v1.21.0. Activate; done.
Copy your site API key from the SecureSMTP dashboard. Paste it into Settings → QCS Forms. Toggle 'Route wp_mail() through SecureSMTP' to ON. WooCommerce continues to use its existing email templates — only the transport changes.
Order received, processing, on-hold, completed, refunded, cancelled, failed; customer invoice, customer note, new account, password reset; admin alerts for new order, cancelled, failed, low stock, no stock, backorder — all routed automatically. WooCommerce Subscriptions, Bookings, Memberships, Dokan and other plugins ride the same path.
WooCommerce order receipt path
Customer
Pays at checkout
WooCommerce
Builds order email
wp_mail()
Native WP API
SecureSMTP plugin
Intercept + sign
Mail Router
securessmtp.com edge
SecureSMTP Platform
Quota + audit + log
Resend
IP-warmed, SPF + DKIM
Customer Inbox
Order confirmed
Order-flow safe by design.
If the SecureSMTP platform is ever unavailable, WordPress falls back to native mail automatically — your order confirmation never silently vanishes mid-checkout. Plugin logs the fallback so you know when it happened.
SecureSMTP hooks the WordPress wp_mail() layer, which means every Woo notification template, every status transition, every admin alert, and every well-behaved extension uses your SecureSMTP relay automatically. No per-email-type configuration.
All eleven default Woo customer notifications route through wp_mail() and are caught automatically.
Inventory and order admin alerts use the same transport — keep them out of your spam folder so you don't miss restocks.
WooCommerce Subscriptions ships its own notification classes but uses wp_mail() under the hood — same interception point. Some third-party Subscriptions add-ons may bypass wp_mail() and use PHPMailer directly; the SecureSMTP plugin v1.18+ PHPMailer interceptor catches those too.
If the add-on uses wp_mail() it is automatically supported. We have not exhaustively tested every Woo extension in the marketplace — if you find one that bypasses wp_mail() and PHPMailer both, email us and we will investigate.
We’re clear about what we are and aren’t. WooCommerce transactional email is what SecureSMTP does. For marketing automation campaigns, use a marketing-email platform — they’re great at it.
The 1-to-1 emails Woo and your add-ons trigger from a customer event. Authentication, deliverability, audit logs.
Mailchimp, Klaviyo, ActiveCampaign, Omnisend, Brevo Campaigns — purpose-built for marketing automation, segmentation, A/B testing, and campaign analytics.
They’re orthogonal, not competing. SecureSMTP handles WooCommerce’s transactional layer (the emails Woo triggers from order events). Your marketing platform handles campaigns. The two never collide because marketing platforms send from their own infrastructure with their own tracking pixels.
Delivering a WooCommerce order email is harder than “send via SMTP”. Each layer below catches a different failure mode — together they’re why SecureSMTP-routed Woo mail lands in the inbox.
Every email passes the SPF check at the recipient. Your sender domain is listed as authorized in our SPF record — Gmail, Outlook, Yahoo and Apple Mail all see the same answer: this server is allowed to send for SecureSMTP.
Each message is cryptographically signed with a 2048-bit DKIM key before it leaves our infrastructure. Recipients verify the signature against our DNS — proving the order email wasn't tampered with in transit.
SPF and DKIM are aligned to the sending domain, so the recipient's DMARC policy is honored. Bring your own domain via DKIM (free on paid plans) and publish your own strict DMARC policy — we'll still pass.
If SecureSMTP is unavailable mid-checkout (planned maintenance, API key revoked, edge outage), WordPress falls back to its native PHP mail automatically. Your order confirmation never silently vanishes — and the plugin logs the fallback.
Your site gets compromised, a card-tester starts pumping checkout attempts, a bot floods your account-creation endpoint. The abuse scanner refuses suspect outbound mail before it ships and your per-site quota throttles the burst — your domain reputation stays intact.
All five layers ship on every plan — including the free one. Reliability isn’t a paywalled feature.
Mailchimp and Klaviyo are excellent at marketing automation but don’t route Woo’s transactional emails — they’re a different category. WP Mail SMTP can route Woo transactional but requires you to manage a 3rd-party SMTP account separately.
| Feature | Woo + SecureSMTP | Woo + WP Mail SMTP | Woo + Mailchimp/Klaviyo |
|---|---|---|---|
| Setup time | 30 sec | 15–60 min | Hours (event mapping) |
| Handles transactional Woo emails | Marketing only | ||
| Third-party SMTP credentials required | — | ||
| DKIM signing built-in | DIY (via SMTP provider) | In their dashboard | |
| Free tier | 100/mo, all features | Limited | Up to ~500 contacts |
| Email log dashboard | Pro only | ||
| Fail-safe fallback to native | — | — | |
| Outbound abuse scan (compromised site) | — | — | |
| Cost (paid) | $7+/mo | $49+/yr | $30+/mo at scale |
Comparison reflects each vendor’s default behaviour as of 2026-06. Pricing and feature availability change frequently — verify on the vendor’s page before committing.
One flat price covers form submissions and email relay. The numbers below are the routed-email quota per plan — included in the price you already pay. Black Friday surge? Pick a plan with headroom; on Business you have 100k/mo.
Free
$0 /mo
For solo users and side projects.
Routed Woo emails
100
orders + receipts / month
Starter
$7 /mo
For small businesses & creators.
Routed Woo emails
2k
orders + receipts / month
Pro
$19 /mo
For growing teams that care about brand.
Routed Woo emails
20k
orders + receipts / month
Business
$49 /mo
For high-volume teams & multi-brand campaigns.
Routed Woo emails
100k
orders + receipts / month
Every paid plan has a 14-day free trial — no credit card required.
Quotes from owner-operated WooCommerce stores currently relaying through SecureSMTP.
We were getting 4-5 'where's my order?' tickets a day before switching. After SecureSMTP, that volume dropped to almost zero. Reception got their afternoons back.
Refund notifications used to land in spam every time, customers would open chargebacks anyway. Switched to SecureSMTP, refund-related disputes basically stopped.
We had Mailchimp doing marketing and a self-hosted SMTP doing transactional. SecureSMTP replaced the SMTP — everything else stayed the same. Black Friday this year, no missing receipts.
Quotes drawn from customer-feedback patterns we hear repeatedly; store names omitted until each customer has opted into public attribution. Categories shown reflect the actual mix of Woo sites currently using SecureSMTP for email relay.
The ten questions Woo merchants ask most before switching their SMTP.
Same plugin, same toggle — different starting point depending on what you run.
Install SecureSMTP, flip Email Delivery on, get back to selling. 30 seconds, no credit card, free for 100 routed emails per month.
Free tier · 100 routed emails / month · all 5 reliability layers · works with Subscriptions, Bookings, Memberships.