They both come with your package, they're both pieces of paper, and they're easy to confuse. But a shipping label and a packing slip do completely different jobs.
The short version: the shipping label gets the box where it's going. The packing slip tells you what's inside.
Side-by-side comparison
| Shipping label | Packing slip | |
|---|---|---|
| Goes where? | Outside the box | Inside the box |
| Purpose | Routing and tracking | Contents verification |
| Who reads it? | Carriers (USPS, UPS, FedEx) | The customer opening the box |
| Legally required? | Yes, can't ship without one | No (domestic). Yes for international customs |
| Includes pricing? | Postage cost only | No, never includes what the customer paid |
| Standard size | 4x6 inches | Varies |
What's on a shipping label
The label on the outside of the box is what every carrier scans to move your package through their network. Every time the barcode gets scanned at a sorting facility or delivery truck, that's the shipping label doing its job.
A shipping label includes:
- Sender name and full return address
- Recipient name and delivery address
- Tracking number and barcode
- Carrier and service type (e.g., USPS Priority Mail, UPS Ground)
- Package weight
- Postage amount
For international shipments, labels also need customs declarations, item descriptions, declared values, and HS tariff codes.
What's on a packing slip
The packing slip is the sheet tucked inside the box. When your customer opens their order, this is how they verify they got everything they ordered.
A packing slip includes:
- Order number and date
- Itemized product list with descriptions
- Quantities of each item
- SKU or product codes
- Shipping method and carrier
- Sender company name and contact info
One thing a packing slip should never include: prices. If the order is a gift, the recipient shouldn't see what the buyer paid. That's what invoices are for.
Packing slip vs commercial invoice
These get mixed up too. A packing slip is a contents checklist with no legal weight. A commercial invoice is a legal customs document required for every international shipment.
| Packing slip | Commercial invoice | |
|---|---|---|
| Legal document? | No | Yes |
| Prices/declared values | No | Yes (required) |
| HS tariff codes | No | Yes |
| Country of origin | No | Yes |
| Required for domestic? | No | No |
| Required for international? | Sometimes | Always |
Do platforms generate these automatically?
Shopify generates shipping labels through its built-in shipping features. For packing slips, you'll need the free Order Printer app or a third-party app since Shopify doesn't auto-generate them natively.
Amazon FBA handles everything on their end. Since mid-2023, Amazon actually stopped including packing slips in most FBA shipments to cut waste. If you're seller-fulfilled, you're on your own for packing slips.
Common packing slip mistakes
- Missing items not noted on the slip (partial shipments without any indication)
- Wrong sizes or colorways listed
- No order number, which makes returns and support a nightmare
- Missing contact info for the seller
At Simpl Fulfillment, shipping labels and packing slips are generated automatically for every order. One less thing to think about. Learn more →