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Restez à l'écoute pour septembre · Septembre 2026

Logistics

Custom address validation for your Shopify checkout.

Packstations, EU postal formats, undeliverable detection — built right into checkout. No per-validation fees.

Book a ConsultationSee What's Included

Fixed Price

No hourly billing

2-4 weeks

Planning, build, tests

Code You Own

Source code + handover

01 — The Problem

Why Generic Address Apps Fail in Europe

European address validation is fundamentally different from US address validation. DHL Packstations and Postfilialen follow non-standard formats that break most validators. Austrian and Swiss postal codes have specific structures. Dutch postcodes use letter-number combinations. French addresses include département codes. Polish addresses split into two postal-code parts.

The result with off-the-shelf US-built validators: 5-12% of European checkouts produce undeliverable orders. The customer pays, the carrier returns the package, you eat the shipping cost both ways, and the customer's perception of your store craters. Per-validation fees from apps like AddressHero (€30-200/month base + per-call fees) make the math worse, not better.

02 — Our Solution

What We Build

A custom address validation that runs in your Shopify checkout and fixes the issues SaaS apps miss:

Packstation & Postfiliale support: Native handling of DHL Packstation numbers (postnummer + station ID), Hermes PaketShop, DPD Pickup, and Austrian Post-Filiale formats.

Real-time autocomplete: Sub-50ms response times with Google/Mapbox/OpenStreetMap as configurable providers — your choice based on cost and data residency.

Country-specific validation rules: DE (5-digit Postleitzahl + Hausnummer required), AT (4-digit), CH (4-digit), NL (4-digit + 2-letter), FR (5-digit + département check), PL (XX-XXX format), and 18+ other EU formats.

Undeliverable detection: Flags addresses that look valid but are known undeliverable (incorrect Hausnummer, demolished buildings, missing apartment numbers in known multi-unit buildings).

Suggestion engine: When a customer enters a malformed address, we suggest the most likely correct version inline — improving completion rates by 8-15%.

03 — For Your Market

Coming September 2026: Free Forever

We're building a free-forever Shopify address validation app, launching publicly in September 2026. It will cover the most common EU validation needs at zero cost. Read the launch announcement and reserve early access.

For stores with custom requirements — specific carrier integrations, Packstation logic, deeper international support, ERP/Wawi handoff — the custom build is the right path. Many of our clients install both: the free app for general validation, the custom build for the edge cases that move the most revenue.

04 — Replaces

Replaces Apps Like

AddressHero (€30-200/month + per-validation fees), PostCo, Address Validator+ ($19-99/month), and DACH-specific tools that bolt onto checkout. Most stores running these spend €600-3,000/year just on validation. Worse, almost none correctly handle Packstations — meaning the apps you're paying for actively let undeliverable orders through.

FAQ

Frequently Asked Questions

Does this work with the Shopify default checkout, or do I need a custom checkout?

Both. We use Shopify's official Checkout Extensions framework so the validation runs natively inside the standard checkout — no custom checkout build required. For Plus merchants on customized checkouts, we integrate at the checkout extension level and at the order webhook layer for redundancy.

How does this compare to your free September 2026 app?

The free app handles the most common EU validation needs (postal code format, country-specific structure, basic Packstation detection) at zero cost — it's the right starting point for most stores. The custom build is for stores that need specific carrier integrations, deep ERP/Wawi handoff, custom suggestion logic, or non-standard address types. Many clients use both: free app for general checkout, custom for edge cases.

How much does undeliverable address rate impact revenue?

For a store doing 5,000 orders/month with a typical 7% undeliverable rate, that's 350 returned packages monthly — €5-12 in shipping cost each way (€3,500-8,400/month in pure shipping waste), plus customer service time, plus the lifetime-value loss of customers who don't return. Custom validation that brings undeliverable rate from 7% to 1-2% typically pays for itself within 90 days.

Ready to cut your app stack?

A 30-minute call. We walk through your current app stack and identify concretely what can be replaced with a custom build — and what shouldn't.

Book a Consultation

2-4 weeks · Fixed Price · Code You Own