Boys Swim Trunks (or underwear!) Pattern and Tutorial


I have finally got around to making Harry some new swimming trunks the night before his school holiday swimming lessons!

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There they both are ready for their lessons in their handmade togs (swimwear for non-kiwi’s!).

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Harry’s swim trunks are not lined as the fabric is very thick and has no risk of clinging or being see-through.  The fabric came from Spotlight and was is called ‘Scuba’, in case you were wondering!

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I was pretty pleased how these turned out so I thought I had better share them with you all.  But Harry doesn’t need anymore swim trunks right now…so I made them out of cotton lycra you can’t have too many pairs of underwear!  Just for the kiwis, reminded me of that Tip Top ad, undies, undies, togs ☺



What you’ll need

  • Stretchy Fabric
  • 25mm (1”) Elastic – 53cm (21”) for size 6
  • Overlocker (can use zigzag on standard machine)
  • Pattern – Free PDF in size 6.


Step 1 – Print Your Pattern

Luckily for you there is now piecing together pages this time, all the pieces are small enough to fit on single pages!  Just print and cut them out.


Step 2 – Cut Fabric

Decide whether you want (or need!) to line your swim trunks/underwear.  If not lining cut one of each pattern piece, and two strips for the leg holes.  If you are lining cut and extra front piece and crotch piece.

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You can see I have two front and two crotch pieces for lining out of the same fabric.

You will need to cut the two strips pictured too.  The dimensions are 4cm (1 5/8”) by 33cm (13”).  If your child has slim or not so slim legs than you can adjust this piece to suit.  Harry is probably about an average size 6, and this size fits just right.


Step 3 – Attach Crotch to Front Piece(s)

I will use black thread on these so your can see what I have done.  You can use matching or contrast thread even a pop of colour…just do what you like!

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Pin the crotch pieces to the front pieces (just one if not lining).  With the right sides facing each other.

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I used the overlocker for this but you can use a zigzag stitch on a standard machine too.

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Here are both front/crotch pieces wrong sides facing.


Step 4 – Attach Back Piece

Now at this point I had a bit of a blonde moment, I am prone to those from time to time!  I was still thinking of the unlined pair and attached the back piece the same way.  So there is a seam inside this pair that doesn’t need to be there.

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I pinned like above and overlocked together.  But a better way would be to pin the back piece in between the two crotch pieces.  See chart below!

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Make sure the Front pieces are right sides facing each other (or against the back piece) in the stack.

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As you can see my seam is on the inside of the trunks if you follow the steps in the chart then yours should be neatly hidden inside like the front seam.

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I decided to topstitch mine ( I did for the unlined version too), just to keep it sitting flat and prevent it from being scratchy.


Step 5 – Side Seams

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Time to sew the side seams.  Line up the sides with the trunks right sides facing each other ( inside out!).  Pin in place and overlock together.

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Repeat for the other side.  I decided to topstitch these seams, this is totally optional but it keeps them sitting nicely.

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You can see how the inside seam lays nice and flat.


Step 6 – Leg Openings

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Fold the strips in half with the right sides facing each other, overlock (zigzag) the ends together.

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Fold the strips over to make a double layer tube.  This is the same as many of the cuffs I have sewn (e.g. Upcycled Merino Baby Pants).

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Pin over top of the trunks leg opening with all the raw edges together.

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It is nice to have the seams line up but I find that the thickness of the layers all together can be a bit much for the overlocker to handle.  So I stagger the seams so they are next to each other.

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With the pins in place I flip the trunks inside out as I find it easier to sew on the inside of the leg opening.

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Here you can see what I mean by sewing in the inside of the leg opening.  Take extra care to catch all the layers.

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And here they are, and yes again I am going topstitch them!  Yes it’s optional and you don’t have to at all but I really really like the seams staying put.  And remember you can use a matching or contrast thread colour.

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Step 7 – Waistband

Cut your elastic to size and zigzag the ends together (check out Joining Elastic here)

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Pin into the inside of your waist, taking care to spread the gather with a little more gather at the back than the front.

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I used the overlocker to attach the elastic but you can zigzag if you prefer.  Just sew right on the top edge and make sure you catch both layers.

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Fold over the waistband and pin in place.

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Zigzag on top of the seam you used to join the elastic, stretching gently as you go to keep the fabric smooth.

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Now just a few more shots of them in action!  He wouldn’t take them off said they were nice and comfortable and wore them for the rest of the day.  Best reward for a sewing Mum ♥

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Girls Swimwear (Togs!)

I had never sewn swimwear (togs for people in kiwi-land) before, I had wanted to but to be honest it seemed a little daunting!  But after finding some gorgeous fabric at spotlight last month I had to give it a go!  Not being quite game enough to start with a pair for me Hannah was up first.

Hannah Togs

A little on the big side but other than that I think they look great!  And more importantly she loves them too ♥  She’s wearing them under her bathrobe since we took the photos it’s really not swimwear weather yet brrr!

I haven’t done a full tutorial on these, I drafted the pattern off her old togs with a lot of editing.  Here are a few photos from along the way.


Cutting the pieces, they looked ginormous!  After I sewed the sides together I waited till Hannah woke up the next morning, didn’t want to have to unpick them!  They were a little big but not too bad, and at the rate that girl grows it’s probably a good thing!


Just in case the fabric wasn’t colourful enough lets add some purple shimmery trim.  Yep that was at Hannah’s request!  With that fabric I doubt anything would clash, it has so many colours in it.  Added the leg trim first, adding quite a bit of gather on the back to allow for bum room.

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I decided on a halter neck, I love the look!  But I stitched it together to prevent it coming undone while swimming, and so she can put them on by herself.  I didn’t fold and sew the straps all the way to the end, I liked the look of the bow without seams.  It is a stretch nylon/lycra so it won’t fray, it’s not as strong but the bow is just decorative since I stitched the straps together before the end of the seams.


Of course I didn’t forget the tag!  You can also see the small zigzag stitch used for the whole pair of togs, that way it is still stretchy.

Hannah Togs

Hopefully summer arrives soon so she can wear them without her bathrobe over the top!

If you want a full tutorial let me know!

Coming Soon…Swim Trunks for Harry!