Granny Square Phone Bag with Joining as You Go – Free Pattern
If you’ve been looking for a fun, practical, and stylish crochet project that actually gets used every single day, this granny square phone bag is exactly what you need. It’s the kind of project that combines nostalgia with modern functionality — a classic granny square motif worked up into a snug little bag that holds your phone, keeps it protected, and looks absolutely adorable hanging from your wrist or tossed into a tote. Best of all, this pattern uses the joining as you go method, which means no tedious sewing at the end. You join each square to the next as you complete the final round, and by the time you’ve finished your last square, your bag is essentially assembled. It’s clever, efficient, and satisfying in a way that makes you want to start the next project immediately.
This pattern is written for a bag that fits most standard smartphones, but you can easily adjust the size by changing your yarn weight, hook size, or the number of squares you make. I’ll walk you through everything — materials, gauge, stitch key, the granny square instructions, the joining as you go technique, and finishing touches like the strap. Whether you’re a beginner who has made a few granny squares before or an experienced crocheter looking for a quick gift project, this pattern is approachable and genuinely enjoyable to work.
Materials You’ll Need
Before you cast on, gather your supplies. Having everything ready at the start makes the process smooth and uninterrupted.
Yarn: Approximately 100–150 yards of worsted weight yarn (size 4). You can use a single color for a clean modern look, or two to four colors for a traditional multicolored granny square aesthetic. Cotton or cotton-blend yarn works beautifully for this project because it has a bit of structure and holds its shape well, which is ideal for a phone bag. Acrylic works perfectly fine too, especially if you want more color variety.
Hook: US size H/5.0mm crochet hook. If you tend to crochet tightly, go up to a 5.5mm. If you crochet loosely, try a 4.5mm. The goal is a fabric that feels firm enough to protect a phone without being stiff.
Notions: Yarn needle for weaving in ends, scissors, stitch markers, and optionally a magnetic snap closure or a button and loop for the top of the bag.
Gauge: One finished granny square should measure approximately 3.5 to 4 inches across after light blocking. Gauge matters here because it affects the final size of the bag, so check yours before diving into a large batch of squares.
Finished Size
The finished bag is designed to fit phones up to approximately 3 inches wide and 6.5 inches tall, which covers most standard and plus-size smartphones. The bag will have a small amount of ease, meaning the phone slides in and out without being too loose or too tight. If your phone is particularly large, you can add an extra row of squares to accommodate it — I’ll mention where to make that adjustment as we go.
Stitch Abbreviations
ch — chain
sl st — slip stitch
sc — single crochet
dc — double crochet
sp — space
rep — repeat
beg — beginning
[ ] — work the instructions inside brackets the number of times indicated
Understanding Joining as You Go
The joining as you go (JAYG) method is a game-changer if you’ve ever spent an afternoon sewing granny squares together and thought, “There has to be a better way.” There is. With JAYG, you complete every round of a square normally until the very last round. During that last round, instead of working slip stitches or chain spaces at each corner and join point freely, you pause at each connection point and join to the corresponding stitch on the adjacent square that’s already been completed.
The result is a seamless, flat join that creates a nearly invisible seam. You can use a flat slip stitch join for a more defined ridge, or a single crochet join for a slightly raised, decorative look. This pattern uses the slip stitch version for a cleaner finish, but I’ll note where you can substitute a single crochet join if you prefer.
The key to JAYG is having your layout planned before you begin your second square. Lay out your finished squares on a flat surface so you know which edges are going to be joined and in what order. Working in a logical sequence — typically left to right in rows, then connecting rows — keeps everything organized.
The Granny Square Pattern
This is a standard four-round granny square with a slightly modified final round for joining. Each square is worked in continuous rounds with a starting chain-3 that counts as a double crochet.
Round 1: Make a magic ring or ch 4 and join with a sl st to form a ring.
Ch 3 (counts as first dc), 2 dc into ring, ch 2, [3 dc into ring, ch 2] 3 times. Join with sl st to the top of beg ch-3. Fasten off if you’re working in multiple colors, or continue to Round 2.
You now have four groups of three double crochets separated by chain-2 corner spaces.
Round 2: Join new color (or continue with the same) in any corner ch-2 space. Ch 3 (counts as first dc), 2 dc in same space, ch 2, 3 dc in same space. [3 dc in next ch-1 space (if you’re working a modified center, or skip to the corner), ch 1, 3 dc in next corner ch-2 space, ch 2, 3 dc in same corner space] 3 times. Ch 1, join with sl st to top of beg ch-3.
Wait — let me simplify Round 2 clearly since the first round has no side spaces:
Round 2 (simplified): Join in any corner ch-2 sp. Ch 3, 2 dc in same sp, ch 2, 3 dc in same sp (corner made). Ch 1. [3 dc in next corner sp, ch 2, 3 dc in same sp, ch 1] 3 times. Join with sl st to top of beg ch-3. Fasten off or continue.
Round 3: Join in any corner ch-2 sp. Ch 3, 2 dc in same sp, ch 2, 3 dc in same sp (corner made). Ch 1, 3 dc in next ch-1 sp (side cluster), ch 1. [3 dc in next corner ch-2 sp, ch 2, 3 dc in same sp, ch 1, 3 dc in next ch-1 sp, ch 1] 3 times. Join with sl st to top of beg ch-3. Fasten off or continue.
You now have two cluster groups on each side and a ch-2 corner space at each corner.
Round 4 (standard, for squares not yet being joined): Join in any corner ch-2 sp. Ch 3, 2 dc in same sp, ch 2, 3 dc in same sp, ch 1. [3 dc in next ch-1 sp, ch 1] twice. [3 dc in corner sp, ch 2, 3 dc in same sp, ch 1, 3 dc in next ch-1 sp, ch 1, 3 dc in next ch-1 sp, ch 1] 3 times. Join with sl st to top of beg ch-3. Fasten off.
You now have a complete granny square with three cluster groups on each side and ch-2 corners.
Make as many complete squares as needed. For this phone bag, you will need 6 squares total — two rows of three squares, which will be folded in half to create the front and back of the bag once joined.
How Many Squares Do You Need
The bag is constructed from 6 granny squares arranged in a 2×3 grid (two columns wide and three rows tall). When the top row is left open for the phone to slide in, you’ll have a finished bag with a neat rectangular shape. The front and back are created by this flat panel, which gets folded at the bottom midpoint.
If your phone is larger or you want a taller bag, make a 2×4 grid (8 squares) instead of a 2×3 grid. The principle of construction remains the same.
Joining Your Squares Using JAYG
Once you have your first square complete, you’re ready to start joining. For clarity, let’s call your first completed square Square A and the square you’re currently working Square B.
Complete Rounds 1 through 3 of Square B normally. On Round 4, work normally until you reach the first edge that needs to be joined to Square A.
At the join point — which will be a ch-1 space on the side of your square — instead of chaining 1 freely, you will: work to the position where you’d normally ch 1, then sl st into the corresponding ch-1 space on Square A, and continue. At the corner, instead of ch 2, you’ll work ch 1, sl st into the corresponding corner ch-2 space on Square A, then ch 1 before continuing with your corner cluster.
Work your way along the entire shared edge this way, pausing at each ch-1 space and each corner to sl st into the matching space on Square A. Once you’ve completed the joined edge, continue working Round 4 on the remaining three sides of Square B freely, with normal chain spaces. Fasten off.
Repeat this process for each new square, always joining along the shared edges with the squares that have already been completed. When you join a square that shares edges with two previously completed squares (like an interior square), simply work joins on both shared edges during that same Round 4.
A helpful tip: use a stitch marker on your completed squares to mark the chain spaces along the edges you plan to join. This way, you don’t accidentally skip a join point, which would cause puckering or uneven seams.
Assembling the Bag
Once all 6 squares are joined into your 2×3 panel, block the panel lightly by misting with water and pinning it flat. This evens out any tension differences and gives you crisp corners.
Allow the panel to dry completely before moving to assembly.
Now fold the panel in half so that the top row of the grid meets the bottom row, with wrong sides facing out (or right sides facing out if you prefer an inside-out seam — I recommend wrong sides out so the seam is on the inside). The fold becomes the bottom of your bag.
Using your yarn needle and a length of matching yarn, whipstitch or single crochet the two side seams together, working through both layers. You can also crochet a slip stitch seam along the sides for a more polished look: hold both panels together, insert your hook through the outermost chain spaces of both panels simultaneously, and slip stitch along the edge.
Once both sides are seamed, turn the bag right side out.
Making the Strap
The strap can be as simple or as decorative as you like. Here are two options.
Option 1 – Chained Wrist Strap: Chain 60 to 80 stitches using a doubled strand of yarn. Slip stitch back along the chain to create a sturdy cord. Attach each end to the inside corners of the bag’s opening with a secure knot or a few whipstitches. This gives a simple, elegant wrist loop.
Option 2 – Crocheted Strap: Join yarn to one top corner of the bag. Ch 3, dc across the opening edge for a firm foundation. On the following rows, work in rows of single crochet or half double crochet until your strap reaches the desired length (typically 10 to 12 inches for a wrist strap, or 40 to 50 inches for a crossbody). Attach the other end of the strap to the opposite top corner of the bag.
Adding a Closure
To keep your phone secure, add a small button and chain loop or a magnetic snap.
For a button closure, sew a decorative button to the center front of the bag just below the opening. On the back flap (if your bag has one) or on a small separate chain loop, create a chain of 6 to 8 stitches, join with a slip stitch to form a loop, and attach it to the corresponding position on the bag’s back. This gives a charming, handmade closure.
Magnetic snaps can be sewn directly to the inside of the bag at the top corners using a few hand stitches, which creates a more secure and modern closure without any visible hardware on the exterior.
Finishing Touches
Weave in all remaining ends securely using your yarn needle. If you worked in multiple colors, you’ll have a few ends per square, so take your time and weave each tail in two different directions for added security.
Give the finished bag a final light blocking. Fill the bag with a folded piece of cardboard or your actual phone to keep it in shape while it dries.
You can also add a small interior lining by cutting a rectangle of lightweight fabric to match the dimensions of your bag, folding and pressing the edges, and stitching it to the inside of the bag with a simple whipstitch. This protects the phone from any rough yarn texture and gives the bag a very polished, finished look.
Tips for Customizing This Pattern
The beauty of a granny square project is how endlessly customizable it is. You can make every square a different color for a truly scrappy, use-up-your-stash version. You can work all squares in a single neutral color for a minimalist, modern look. You can use a variegated self-striping yarn so that each round shifts in color without any yarn changes at all.
If you want a smaller bag for an older model phone or for a card holder, simply reduce your hook size and use a finer yarn. If you want a chunkier, more textured bag, try bulky yarn on a larger hook — it works up incredibly fast and looks dramatic.
You can also swap out the standard granny square for a solid granny square (working double crochets without chain-1 side spaces), a v-stitch granny square, or even a granny square worked entirely in single crochets for a very dense, firm fabric.
Final Notes
This granny square phone bag with joining as you go is one of those patterns that becomes a staple. Once you’ve made one, you’ll want to make them for everyone — in team colors, in your favorite autumn palette, in a cheerful spring brights mix. They’re fast enough to finish in an evening or two, they use up small amounts of yarn beautifully, and they’re genuinely useful in a way that makes the recipient actually use them rather than storing them in a drawer.
The joining as you go method does take a few minutes to learn if you’ve never tried it, but once it clicks, you’ll find it hard to go back to the old way of sewing squares together at the end. It keeps the process lively and gives you immediate feedback on how the finished piece is taking shape, which is one of the most satisfying parts of making any crochet project.
Please share your finished bags if you make this pattern — seeing the color combinations people choose is genuinely one of the best parts of putting a free pattern out into the world. If you have questions about any of the steps, leave a comment below and I’ll do my best to help you out. Happy crocheting!
