PackOS vs ShipStation

Two products, and the margin between them.

No Shopify required. No carrier contract. Connect a store, upload a CSV, or just type an address — then rate shop USPS, UPS, and FedEx, buy in batches, and see exactly what each shipment made or lost. Free account; you pay for labels.

Create a free Labels account Get PackOS Checkout

PackOS Labels is free, always · PackOS Checkout has a 14-day free trial on every plan

This is a factual comparison and it says where ShipStation wins.

The core difference

What each one is built to do

ShipStation is an order-management platform first. It pulls orders from many marketplaces and storefronts into one queue, and its automation rules can set the service, the package and the warehouse before anyone opens the order. Sellers running several channels at once get a lot out of that shape.

PackOS is two products instead. PackOS Labels buys discounted USPS, UPS, FedEx, DHL and Canada Post labels for any store — Shopify, WooCommerce, a CSV from anywhere, or a shipment you type by hand — and it is free, always. PackOS Checkout quotes the real rate at your Shopify checkout after picking the real box. Run both and the margin on each order is calculated for you rather than reconciled by you.

Detailed feature comparison

A side-by-side look at what each platform offers. A checkmark where a capability is built in, and a note where the answer depends on your own setup.

Feature	PackOS	ShipStation
Rates at Shopify checkoutLive carrier rates shown to the customer during checkout, without custom code	Built inPackOS Checkout	See ShipStation for checkout rate options
Bin-packing box selectionDecides which box the order ships in before asking a carrier for a price	Built in	See ShipStation for how packages are set
Discounted multi-carrier labelsBuy labels from USPS, UPS, FedEx, DHL and Canada Post in one dashboard	Built inPackOS Labels	Built inMany carriers; see ShipStation for the list
Order import without writing codeShopify and WooCommerce order import, a CSV from any other platform, or a shipment typed by hand	Built inShopify, WooCommerce, CSV, or manual	Built inMany channels and marketplaces
Shipping margin per orderThe gap between what the customer paid and what the label cost	Built inAutomatic with both products	Depends on what your checkout collects
Free to useWhat you pay before you have bought a single label	Free, always	See ShipStation for plans

ShipStation publishes its current plans, channels and carriers on its own site.

When ShipStation is the better choice

ShipStation is a mature multi-channel shipping platform. There are real situations where it is the right tool for the job.

You sell on many marketplaces and want one order queueShipStation pulls orders from a long list of marketplaces and storefronts into one place to work through. If your day starts by reconciling several channels before anything ships, that queue is the product you are buying, and it is a good one.
You rely on automation rulesShipStation lets you write rules that set the service, the package and the warehouse before anyone opens the order. If your shipping decisions are already encoded that way, those rules are real work that took real time, and they are worth keeping.
You already run ShipStation and it fitsA workflow the people who pack are fluent in is worth something on its own. If ShipStation covers what you send, staying is a reasonable answer — and PackOS Labels is free, always, so you can compare the two on your own shipments whenever you like.

When PackOS is the better choice

PackOS Labels was built for anyone who buys labels — on Shopify, on WooCommerce, from a CSV, or one at a time by hand. PackOS Checkout was built for Shopify merchants who want the rate their customer sees to match the box the order actually ships in. Neither asks you to write code or manage an API integration.

You want accurate checkout rates without codingPackOS Checkout uses bin-packing to determine the right box, then queries carriers with the actual dimensions and weight. Your customers see real rates at Shopify checkout — no development work, no API integration, no custom code.
You want to see your shipping marginWhen PackOS is present at both the checkout quote and the label purchase, it calculates the margin on that order for you. You don’t need to export data, run spreadsheets, or cross-reference two systems to know if shipping is making or losing money.
You want checkout rates and labels from one platformPackOS Checkout returns the rate at checkout and PackOS Labels buys the label. Because both write to the same order, the margin is calculated for you instead of reconciled by you. Use either alone — neither one requires the other.
You need bin-packing for box optimizationPackOS Checkout doesn’t just look up rates — it first determines which box to use based on the items in the order. This means checkout rates account for dimensional weight accurately, reducing overcharges and undercharges.

Switching

Moving from ShipStation

Connect your Shopify or WooCommerce store, or import a CSV of your open orders.
PackOS Checkout installs separately from the Shopify App Store when you want the rate at checkout too.
Your wallet starts at zero; you pay only for the labels you buy, and there is no subscription to set up.
Nothing to cancel on the PackOS side. Cancel with ShipStation on their terms whenever you are ready.

The key differentiator

Where margin comes from

PackOS Checkout quotes the rate at your Shopify checkout using the real box, so the label side already knows what was collected for shipping. That is the number margin is measured against.

For merchants who use flat-rate or free shipping, margin visibility might not matter. But for merchants who pass carrier rates to customers at checkout and want to know whether shipping is a profit center or a cost center, this gap is worth weighing. A label tool on its own only ever sees the label side of the equation. Run PackOS Checkout and PackOS Labels together and PackOS sees both.

One order · Two numbers · One difference

Quoted at checkout

What the customer paid you to ship it

PackOS Checkout

Paid for the label

What the carrier charged you to move it

PackOS Labels

Margin

The difference, recorded on every order

Both products, on the same record

Run either product on its own. Run both and the same order carries both numbers.

FAQ

PackOS and ShipStation, answered

Do I need a Shopify store to use PackOS Labels?

No. Connect a Shopify or WooCommerce store, import a CSV from any other platform, or create shipments by hand with no store connected at all.

What does PackOS Labels cost?

Nothing. PackOS Labels is free, always — no monthly subscription and no markup on postage. You pay the carrier price shown for each label you buy. Wallet credit is spendable on PackOS labels.

How does PackOS Checkout know which box to quote?

You load your box library into PackOS Checkout — the same boxes you actually use to pack orders. When a customer checks out, PackOS runs a 3D bin-packing algorithm across the cart items and picks the optimal box. That box's dimensions are what gets sent to the carriers for the rate quote.

Do I need PackOS Labels to use PackOS Checkout?

No. PackOS Checkout works standalone — you can keep buying labels wherever you buy them today. However, using PackOS Labels alongside Checkout means the rate your customer saw at checkout is the rate you pay for the label. No margin leak between quote and label.

Find out what shipping is really costing you.

PackOS Checkout quotes the real rate at your Shopify checkout. PackOS Labels buys discounted labels for any store and shows the margin on each one. Start with either.

Create a free Labels account See Checkout + Labels together

14-day free trial on every Checkout plan
Labels is free, always