Turn online orders into offline loyalty.
Trigger thank-you postcards, win-back drops, and VIP mailers off any Shopify or Klaviyo event. Same API, same 24-hour print pipeline, tracked end to end so you can attribute every piece back to revenue.
Capabilities
Built for the retention stack you already run.
- Shopify and Klaviyo native
- Wire MailStream into your existing flows. Trigger postcards from order events, segment lists, or any Klaviyo flow with a webhook. No middleware required.
- Order-event triggered sends
- Fire a postcard on order placed, order delivered, second purchase, or VIP threshold. Every send carries order metadata for clean attribution.
- Lapsed-customer win-back
- Re-engage shoppers who have not opened email in 60 days. Physical mail gets opened at 5 to 9x the rate of marketing email and converts the dormant cohort.
- Seasonal and promo blasts
- Upload a CSV or pull a segment, schedule the drop date, and let the pipeline handle the rest. Holiday catalogs, Black Friday teasers, anniversary offers.
- VIP and loyalty mailers
- Reward your top 1 percent with branded handwritten notes or premium thank-you cards. Tier-aware sends keep top customers locked in.
- Full delivery tracking
- Intelligent Mail barcodes on every piece. Track print, USPS handoff, in-transit scans, and delivered status via webhook back to your stack.
- 5-9x
- Higher open rate than email
- 24hr
- Print-to-ship turnaround
- 25-40%
- Repeat-purchase lift on thank-yous
- 100%
- Pieces tracked via USPS
- Order-event triggered
- Fire a postcard from order placed, delivered, or any custom Shopify or Klaviyo event. No batch exports.
- Variable data per piece
- Merge first name, order number, recommended product, or QR coupon into every postcard at no extra cost.
- CASS-verified addresses
- Every address validated before printing. Invalid or undeliverable addresses flagged so you never waste postage.
- 25+ years of expertise
- Twenty-five years running direct mail at scale. We have seen every edge case in e-commerce fulfillment.
Use cases
From first order to lifelong customer.
- Post-purchase thank-you
- Trigger a branded postcard after every order. Customers who get physical follow-ups show meaningfully higher repeat purchase rates than email-only cohorts.
- Abandoned-cart win-back
- Fire a postcard 7 to 14 days after a cart abandon. A different channel breaks through inbox fatigue and recaptures revenue email cannot reach.
- VIP and loyalty tier drops
- Send premium cards to your top spenders on milestones, birthdays, or tier upgrades. Keeps your most valuable customers engaged off-platform.
- Holiday and seasonal campaigns
- Drop Black Friday teasers, holiday catalogs, and back-to-school offers on the dates that matter. Schedule once, deliver thousands.
- AI-agent triggered offers
- Let an agent decide when a postcard is the right move. MCP server connects MailStream to Claude, GPT, or any compatible model.
- Replenishment reminders
- For consumables, trigger a reorder reminder card timed to the empty-bottle window. Subscription replacement at a fraction of the email-only conversion cost.
What everyone is saying
Trusted by e-commerce teams that take retention seriously.
We layered MailStream onto our Klaviyo win-back flow and recovered 18% more dormant revenue in the first quarter. The Shopify trigger took us a single afternoon to set up.
Daniel H.
Director of Retention, Northbridge Outfitters
Thank-you postcards after every order have become our highest-ROI repeat-purchase lever. Customers literally email us photos of the card.
Olivia W.
Head of Lifecycle, Trailmark Goods
The webhook delivery confirmations let us tie every postcard back to revenue in our BI stack. It is the first direct mail vendor we could actually attribute.
Mia R.
VP of Growth, Beacon Apothecary
Brands on Shopify, BigCommerce, and headless stacks use MailStream to add a physical channel to email and SMS, without juggling new vendors.