One-line definition: automating customs forms means capturing the data a cross-border parcel needs - product descriptions, HS codes, values, your EORI and tax numbers - once, then generating the commercial invoice and CN22/CN23 declarations from your order data automatically, instead of typing each one by hand.
Customs paperwork is the part of international shipping that punishes you for growing. At five orders a week you can type each customs form by hand. At fifty, it's an hour a day of transcribing product descriptions and values, and every typo is a parcel that gets stuck at a border while your customer wonders where it is. The good news is that almost none of it needs to be manual - the data already lives in your Shopify orders. This guide covers what the forms are, why automating them matters more in 2026 than it did a year ago, and how to set it up.
Why this matters more in 2026
For years, low-value parcels slipped across borders with minimal customs friction thanks to de minimis thresholds - the value below which a shipment was exempt from duties. That era is ending, fast.
In the United States, the $800 de minimis exemption was eliminated on 29 August 2025. Shipments that used to clear with almost no paperwork now require formal customs entry, duties, and taxes. In the European Union, the €150 customs-duty exemption is being removed from 1 July 2026, with a temporary simplified duty (reported at around €3 per item) applying to low-value parcels until the EU's Customs Data Hub comes online in 2028. The UK is set to remove its £135 duty relief by 2029, and Norway's VOEC scheme already requires sellers to handle VAT on low-value goods.
The practical upshot is the same everywhere: more of your parcels now need complete, accurate customs data than before. The paperwork burden is going up at exactly the moment manual processing becomes least affordable. Automating it isn't a nice-to-have anymore - it's how you keep shipping across borders without drowning in forms or watching parcels pile up in customs holds. If you want the background on how these thresholds work, our explainer on the de minimis threshold goes deeper.
The customs forms you actually need
Before you automate anything, it helps to know what you're automating. A cross-border shipment generally travels with some combination of these.
The commercial invoice. The core customs document. It declares what's in the parcel, its value, the sender and receiver, and the terms of sale. Customs authorities use it to assess duties and taxes. Our guide to the commercial invoice covers what each field means. For shipments sold before they're made or shipped without a sale, a pro forma invoice does a similar job.
CN22 and CN23 declarations. These are the postal customs forms for goods sent through national postal operators. The CN22 covers lower-value items and CN23 higher-value ones, and they need to be filled in correctly and legibly or the parcel gets delayed. Best shipping apps generates the CN22 and/or CN23 declarations automatically if they are needed. If you do not have access to a shipping app that generates these you can use our CN22/CN23 custom declaration tool for free.
HS / tariff codes. Every product needs a Harmonised System code that tells customs exactly what it is, so the right duty rate is applied. Getting these right matters for both compliance and cost - and finding the right tariff code is one of the most common places merchants go wrong.
Your EORI number. If you ship to or from the EU, you need an EORI number - a trader identifier customs uses to track your shipments. It goes on your export documentation.
Tax registrations: IOSS and VOEC. For low-value goods into the EU, the IOSS scheme lets you collect VAT at checkout so the customer isn't surprised by a bill on delivery. Norway's VOEC does the equivalent. These numbers need to travel with the shipment data.
If any of that felt like a lot, that's the point: it's a lot to get right by hand, on every order, without a single fat-fingered value or missing code. For the full picture of how these fit together, our guide on managing international shipping on Shopify ties them into one workflow.
Where the manual process breaks down
Doing customs forms by hand fails in three predictable ways, and all three cost money.
The first is time. Transcribing product names, quantities, values, weights, and codes into a separate customs form for every international order is pure repetition - and it scales linearly with volume, so it gets worse exactly as your business gets better.
The second is errors. A mistyped value, a wrong or missing HS code, an outdated EORI - any of these can get a parcel held at customs. A held parcel means a delayed delivery, an anxious customer, a support ticket, and sometimes a return-to-sender you pay for twice. The duties, taxes, and VAT get miscalculated when the underlying data is wrong, and your customer is the one who feels it.
The third is inconsistency. When forms are filled by different people on different days, they drift. One person rounds values differently, another describes products vaguely ("clothing" instead of "women's cotton t-shirt"), and vague declarations are exactly what customs officers stop to question.
How to automate it
The core idea is simple: the information a customs form needs already exists in your Shopify store. Automation is about capturing it once, in the right place, and letting software assemble the forms.
Store HS codes at the product level. Add the correct HS/tariff code to each product (or variant) once, as part of your product data. From then on, every order that includes that product carries its code automatically - no lookup at packing time.
Hold your identifiers once. Your EORI, IOSS, and VOEC numbers don't change order to order. Store them in your shipping setup so they're applied to every relevant shipment automatically rather than remembered and re-entered.
Capture clean product descriptions and country of origin. Precise descriptions and accurate country-of-origin / rules-of-origin data on your products feed straight into the declaration and keep customs from second-guessing it.
Generate the documents from the order. With that data in place, a shipping app builds the commercial invoice and CN22/CN23 from the order automatically when you create the shipping label. Packrooster Shipping does exactly this - it generates the customs documents as part of the label-creation flow, pulling the product, value, and identifier data you've already stored, so the paperwork is produced and printed alongside the label instead of typed out separately.
Collect VAT at checkout where you can. Using IOSS for EU orders (and VOEC for Norway) means the tax is handled up front, the customer isn't hit with a surprise fee on the doorstep, and the shipment clears faster. That's fewer refused deliveries and fewer angry emails.
A short checklist to get started
If you ship internationally and you're still filling forms by hand, work through this in order:
First, add HS/tariff codes to every product you sell abroad. Second, register for and store the identifiers your destinations require - EORI for the EU, IOSS for EU VAT, VOEC for Norway. Third, tighten your product descriptions so each one reads like something a customs officer can classify at a glance. Fourth, move label and customs generation into one flow so the documents come off the same action. And if the volume or the rules ever get genuinely complex - high values, restricted goods, unusual routes - our guide on when you need a customs broker covers where a human specialist earns their fee.
Customs paperwork will never be the fun part of running a store. But in 2026, with exemptions disappearing and more parcels needing full declarations, it's the part most worth taking off your team's hands - and the data to do it is already sitting in your orders.
