How to Fold an Envelope from Paper

What You’ll Need

A rectangular sheet of paper (standard letter size or A4 works best)
A flat, clean surface to work on
Optional: a bone folder or the edge of a ruler to make sharp creases
Optional: a seal (wax, sticker, or washi tape) to keep the flap closed

Step-by-Step

Orient the paper. Place the paper flat on your surface in landscape orientation (long edges at the top and bottom). If your paper has a printed side, keep it facing down so the blank side is up.
Fold the bottom edge up. Bring the bottom edge up to meet the top edge, but do not crease yet. Instead, pinch the center and fold the bottom edge up about one-third of the way. Crease firmly. This bottom flap will become the back of the envelope.
Fold the top edge down. Bring the top edge down over the bottom flap, leaving a small gap (about 1 cm or half an inch) between the top edge and the bottom fold. Crease well. The top flap will become the envelope’s front flap.
Unfold the top flap. Open the top flap back up so you have a clear view of the bottom flap. You should see two crease lines: one from the bottom fold and one from the top fold.
Tuck the sides. Fold the left and right edges of the paper inward along the creases, creating two triangular flaps. These will form the envelope’s side gussets. Make sure the points of the triangles meet in the middle without overlapping.
Refold the bottom flap. Fold the bottom flap back up along its crease. The side triangles will now be tucked inside the bottom flap, creating a pocket.
Insert your letter and seal. Place your letter or card inside the pocket. Fold the top flap down over the pocket. Tuck the point of the top flap into the pocket’s opening, or use a seal to keep it closed.

Common Mistakes

Folding the paper in half instead of thirds. If you fold the bottom edge all the way to the top, you’ll end up with a card, not an envelope. Always stop about one-third of the way.
Creasing too lightly. Weak creases make the envelope floppy and hard to tuck. Use a bone folder or your thumbnail to press down firmly.
Making the top flap too short. If the top flap doesn’t reach the bottom fold, it won’t tuck in properly. Leave a small gap, but not too much—about a centimeter is ideal.
Forgetting to unfold the top flap before tucking the sides. If you don’t unfold, the side folds will be trapped and the envelope won’t open properly.

Tips

Use a square sheet of paper for a smaller, more traditional envelope shape. Fold it diagonally to create a diamond, then follow the same steps.
For a more secure seal, use a small piece of double-sided tape or a glue stick on the top flap before tucking it in.
If your paper is thin, line the inside with a piece of scrap paper for extra durability.
Decorate the envelope with washi tape, stamps, or hand-drawn designs before folding to make it personal.
Practice with scrap paper first to get the hang of the folds before using your best stationery.

Troubleshooting

The envelope won’t stay closed. If the top flap doesn’t tuck snugly, the paper may be too thick or the flap too short. Try using a seal or a small piece of tape to hold it closed.
The sides bulge out. This happens when the side triangles are too wide. Trim a little off the edges before folding, or use a narrower sheet of paper.
The envelope is too small for your letter. Fold your letter to a size that fits within the pocket, or use a larger sheet of paper. Alternatively, fold the letter in half or thirds to make it smaller.
The paper tears along the crease. This is common with thin or dry paper. Use a lighter touch when creasing, and consider using a heavier paper stock.
The envelope looks lopsided. Make sure your initial folds are parallel to the edges. Use a ruler to measure equal thirds if you’re having trouble eyeballing it.

Frequently Asked Questions

Can I use any size of paper?

Yes, but the proportions matter. A rectangular sheet (like letter or A4) works best. Square paper will give you a smaller, more compact envelope. Just adjust the fold positions to match the size.

Do I need glue or tape?

No, the tuck-and-fold method keeps the envelope closed without adhesive. However, if you want a more secure seal, you can use a sticker, wax seal, or a small piece of tape.

How do I make a bigger envelope?

Use a larger sheet of paper, such as A3 or legal size. The folding steps remain the same; just scale up the fold positions proportionally.

Can I reuse the envelope?

Yes, if you open it carefully along the creases, you can flatten it and fold it again. The creases may weaken over time, so it’s best for light use.

What’s the best paper for making envelopes?

Medium-weight paper (around 80-120 gsm) is ideal. It’s sturdy enough to hold its shape but thin enough to fold easily. Cardstock works too but may be harder to crease.

How do I address the envelope?

Write the recipient’s address on the front (the side with the top flap) and your return address on the back (the side with the bottom flap). Use a pen that doesn’t bleed through the paper.

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