Essential Pockets Every Bag Maker Should Know

In my new book, Essential Bag Making Reference Tool, I walk through the two pockets every bag maker should master: Slip Pockets and Zipper Pockets.

These foundational pockets appear in nearly every bag pattern—totes, crossbodies, backpacks, wallets—and learning how to construct and customize them opens the door to endless creativity.

Today’s post gives you an overview of each pocket type, variations you can try, and the tools and materials that make a big difference in your results. Consider this your introduction to essential pockets, and your full step-by-step instructions are waiting inside the book! 

Pockets don’t just add function—they influence the entire interior of a bag. The right pocket:

• Keeps your bag organized

• Adds stability to your lining

• Reinforces high-use areas

• Helps your bag hold its shape

• Makes your handmade bags feel polished and professional

Even simple pocket upgrades—like better interfacing or a hardware closure—can take your bags from “nice” to “wow!”

How Slip Pockets Work

A slip pocket is simply a rectangle of fabric sewn to the lining or exterior of a bag along three sides. But to create a clean, professional-looking pocket, you’ll want to pay attention to:

• Cut size (based on the shape and structure of your bag)

• Top edge finishing (folded, bound, or turned

• Interfacing for stability

• Topstitching for reinforcement

• Optional divisions for organization

Slip Pocket Variations

Even though they’re simple, slip pockets offer endless possibilities. Here are a few ways to elevate them:

Add a Hardware Closure

A basic pocket becomes instantly more polished with a secure closure. Some favorites include:

• Flip Locks (Drop Locks):
  Made of a base plate and flip unit. The flip rotates down into the plate to lock the pocket closed. Perfect for securing pocket flaps on wallets, bags, and accessories.
  

• Tuck Catches (Press Locks / Thumb Catches):
  A two-piece lock where the tuck unit compresses and slides into the base. Available in many shapes and sizes—small versions are ideal for internal pockets; larger ones work beautifully on backpack or handbag flaps.
  

• Magnetic Snaps:
  The quickest way to add a closure. Great for slip pockets on totes or interior compartments.

• Line Snap Fasteners:
  Snap-together discs used for pockets, flaps, adjustable straps, and small accessories. They require a specific installation tool for secure placement.

Create Pocket Dividers

Adding one or more vertical stitch lines divides a larger pocket into compartments—great for pens, phones, sunglasses, or small accessories.

Double Topstitching

For added durability, try stitching a second reinforcement line ¼" from the side and bottom edges.

Custom-Sized Zipper Pockets

One of the most useful skills covered in the book is learning how to size zipper pockets based on the bag’s design. You’ll be able to:

• Adjust pocket width and height

• Place the pocket where it functions best

• Add the pocket to either the exterior or interior lining

• Ensure the pocket doesn’t interfere with seams or boxed corners

A Special Technique: Turn Through the Pocket

The book also teaches you how to install a zipper pocket that doubles as the turning opening for the entire bag. This lets you turn the whole project right-side-out through your zipper pocket—no lining gaps to stitch closed!

Ways to Elevate Zipper Pockets

Want your zipper pocket to stand out? Try:

• Printed zipper tape (stripes, dots, florals, or geometric prints)

• Striped or two-tone zipper tape

• Colorful zipper coils like Tula Pink hardware coils

• Contrast zipper pulls for a unique accent

• Pocket covers or flaps when you want a sleek, concealed look

Your New Favorite Tool: The Hot Ruler

A hot ruler (or hot hemmer) is a heat-resistant measuring tool that allows you to iron directly on it. When you’re pressing pocket edges, folds, or zipper windows, a hot ruler ensures crisp, accurate results—especially on curved or narrow hems.

No matter which pocket style you’re making, interfacing plays a huge role in the final look and durability.

Here’s why it matters:

• Prevents stretching on pocket edges

• Supports closures like snaps, locks, or rivets

• Keeps lining fabric from sagging

• Adds stability to high-use areas

• Helps pockets withstand daily wear

Best practice: Interface the lining fabric itself and add extra interfacing behind hardware placements. This is the key to pockets that hold their shape beautifully over time.

But there’s one exception—and it’s a game changer.

A Helpful Hack: Use Turtle Tex Instead of Interfaced Fabric

Turtle Tex isn’t a standard quilting cotton. It’s a coated cotton that’s naturally:

• Water-resistant

• Soft yet structured

• Durable enough for everyday lining use

• Resistant to stretching

• Smooth and stable—perfect for pockets

Because of its built-in structure, you can skip interfacing altogether when using Turtle Tex for slip pockets or zipper pockets and still achieve that crisp, supportive finish.

This makes it especially helpful for:

• Beginner sewists who want fewer steps

• Speeding up bag construction

• Reducing bulk in tight areas

• Creating linings that look clean and professional

• Projects where durability is key (like backpacks or travel bags)

Pressing Tip

When pressing Turtle Tex:

• Use a cool or synthetic iron setting on the cotton side.

• Avoid pressing directly on the coated side.

• If you need a sharp fold (like along a pocket edge), place the coated side against itself and press gently—the coating lightly “fuses” to itself, helping the fold hold its shape without any additional interfacing.

This little trick gives you beautifully crisp pocket edges with minimal effort.

Slip pockets and zipper pockets may seem simple, but together they form the backbone of a well-designed bag interior. Once you learn the essential techniques, you can build on them with hardware, specialty materials, creative topstitching, and unique zipper details.

And that’s exactly why I included both pocket techniques in my new book—these two foundations support every other pocket variation you’ll explore.

Every detail—cutting, measuring, pressing, interfacing, hardware installation, and troubleshooting—is fully explained inside my new book: The Essential Bag Making Reference Tool. This book is a compact, practical guide designed to help you sew polished, professional bags with confidence!

It’s small enough to sit next to your sewing machine or tuck into a project bag—and packed with the knowledge you’ll reach for again and again.