WooCommerce & Packing Slips

Heading image with blog title and printer icon

Including a packing slip with customer orders accomplishes a few things, but you can print them in many different ways, depending on your processes. In this article, I’ll discuss why you might choose to add packing slips to your order fulfillment process and how to do it with WooCommerce. Whether you’re shipping hundreds of orders per day or just a few per week, I’ve got a solution for you.

Why Packing Slips?

Image of a packing slip printed on a thermal 4" x 6" label.
A WooCommerce packing slip printed with a Zebra ZQ630 with custom ZPL.

First of all, when I, personally, see a packing slip in a package I receive, I immediately feel that the contents of the package are more likely to be the actual things I expect. A packing slip says that the vendor incurred additional time and expense to include an accounting of what the order should contain.

Next, and more important to your company, adding a packing slip to the order fulfillment process increases fulfillment accuracy. During the lifecycle of an order-in-process, a printed packing slip can follow an order from picking all the way to final packing and shipment. At each step in the fulfillment process – picking, binning, quality control, and packing – a packing slip can be referenced to ensure order accuracy and completeness.

Low Volume

If you’re using WooCommerce without a third-party shipping/fulfillment system(e.g. ShipStation, ReadyShipper, etc.), the simplest way to get started printing packing slips is to add a WordPress plugin. There are several plugins out there, so I won’t recommend a specific one here. The choice here really boils down to the features you need.

Whichever extension you choose, they’ll most likely include just a basic 8.5″ x 11″ packing slip that you can print with a normal inkjet or laser printer on standard paper.1Although you could print these on thermal printers at a 4″ width, the text becomes unreadable.

If you have a shipping system integrated with WooCommerce that you use to retrieve shipping quotes and print shipping labels, most of them include a way to print a packing slip as well. ShipStation, for instance, can be configured to print a packing slip when the shipping label is printed.

If you’re using a normal printer, you can print on special 8.5″ x 11″ paper with two, die-cut 4″ x 6″ labels. One half is for the shipping label, and the other is left in place to serve as the packing slip.

If you’ve upgraded to a 4″ x 6″ thermal label printer, you can also configure your shipping software to print an extra packing slip label immediately after the shipping label is printed. Just leave the liner on the packing slip label, and it works just fine. If you print in batches, however, this can become a bit of a mess, as it’s not immediately obvious which shipping label a specific packing slip should be paired with.

High Volume

Image of Zebra mobile thermal printers.
Just a couple of the Zebra mobile thermal printers I have.

At this level, order fulfillment efficiency becomes very important, and the processes become a little more complicated. Time is money here, so having order pickers going back to a station with a big printer isn’t efficient. Here’s where Zebra mobile thermal printers shine.

At lower volumes, printing in batches works for a while, but presents somewhat of a paradox. Using the example above, ShipStation(and similar software) will print the packing slip at the same time it prints the shipping label.

However, printing a shipping label requires a few things that may not yet be known with certainty. One example is the shipping weight. Sure, individual product weights can be summed, but what about packing material? I’ve written item packing algorithms, but even the best ones have to make assumptions and, due to the nature of the problem they are solving, must overestimate by a good amount. Also, many companies these days throw in promotional materials/items that increase the shipping weight. Getting the gross weight at final packing is best, if only to validate algorithmic decisions and guide future improvements.

Another potential variable here is the shipping carrier and service. Depending on your internal cut-off times and actual shipping provider pick-up times, a non-default shipping carrier and/or service might be needed to get the order to the customer in a timely manner. Again, although these things can be accounted for in code, having the shipping method set prior final packing can complicate things.
With these two potential issues alone, it’s easy to see why you might not engage your shipping software until after an order has been picked and packed.

Costs

Printing packing slips does increase costs. How much? It depends on which of the above methods you choose.

For the standard 8.5″ x 11″ packing slips, you can always print on normal paper with an inkjet or laser printer. The costs here are the printer consumables, i.e. ink or toner, and the paper.

For thermal printing, there’s no ink or toner, just paper. You can also go mobile with some models, increasing process efficiency.

What’s Next

Taking full ownership of the process here involves custom software to create your packing slips on the fly. You can’t ctrl-P on a mobile device, and even if you could, results would be erratic. This can be solved by using the Zebra Programming Language(ZPL) which is a common language understood by most thermal printers. Using ZPL, you can format a printed document to your exact specifications. Barcodes, text boxes that handle overflow, dividers, borders, rotations, and images are all doable with ZPL. You can also have custom thermal label rolls manufactured to your specifications with your logo, table borders, and more.

Usually, packing slips can serve as a “gateway drug” to bigger and better things along the road to better order fulfillment processes and warehouse operations in general. One possible next step is using the same printers to label products, warehouse racks, palletized items from vendors, license plating, etc.

Want to talk with someone who has experience integrating Zebra mobile computers and printers into your warehouse operations? Contact me.