I always use the next size up. For a 20x20 cover, I would use a 22x22 insert.

Agree with tinam61.

For my recent accent pillows, I made covers that were 18 x 18 (finished size). I used 20 x 20 inserts.

I cut the fabric 19 x 19 and used a 1/2" seam allowance which gave me a 18 x 18 finished size.

I also used a new technique (learned from another GW post)
to round out the pointy corners of the pillow a bit.
(see link below).

Are you making cushions or accent/decorative pillows? I think of a cushion as something to sit on, or to be the back of a chair or sofa.

Here is a link that might be useful: Pillow Corners - Less Pointy

I know conventional wisdom says to make the covers 2" smaller per side than the inserts. I made pillows for DD's guest room bed. I had 24x24 feather inserts so I made the pillows 22x22. They look terribly over-stuffed.

Next time, I'll start with fabric cut the same size as the insert, plus seam allowance. Then I'll pin, and baste if necessary, to see how much it needs to be taken in to make a good-looking pillow.

bbstx - I have never had that problem. I started using the larger inserts after buying some covers from an etsy seller and that is what she suggested. It has always worked great for me; I think the pillows look so much better.

Laurie! I have never seen that technique! How interesting. I have heard the pointy corners referred to as rabbit ears. LOL
What I do is round the corners. I have tissue paper patterns for my different pillow sizes and I trace out a square in the desired measurements. Let's say 20 x 20. Then I take a small plate, saucer, etc. and use that to trace a rounded "corner" instead of pointed. Works great! I'm going to try the method you shared and see how that looks. I love pillows and change out covers often.

I always advise my clients to get inserts one size up from the size of the pillow cover for the best results. That way the pillows are firm and corners filled.

I second the non-pointy corner pillow advice from laurie_2008. I purchased a clear plastic pillow template that includes the 1/2" seam allowance and eliminates the "dog ears." It's magic.

As others have said, I usually make my pillow covers 2" smaller than the 90/10 down/feather inserts I often use. Not sure if that would work for the ultra-puffy poly inserts these days so maybe that's where things go wrong for some folks.

rgustafs

I have read, also, that (as rgustafs mentioned) you need to consider the insert material (soft down, as opposed to firmer poly).
Below, is another good link that helped me when experimenting with the less pointy corners.

Here is a link that might be useful: Lifes Sweet Essentials

Thank you all for your good advice.
I am now going to buy a bit bigger inserts for my covers.
I love coming here and asking questions, you are all so helpful.

I don't care for the very stuffed pillow look or feel. I love decorative pillows but my family likes to use them, and the overstuffed, "sausage casing fit" pillows are not comfortable under one's head. So the knife edge and flange pillows we have now are somewhat floppy by design.

The relaxed box pillow is what we are using downstairs in the new area. An added benefit is that its allowing me to use two fabrics, one on the faces and another on the box part. The only downside is that there is a lot more welting to make. (I'm not making them myself but somebody is making more welting, lol.)

That tip Laurie posted the link to works great. It was in my Singer sewing books from years ago and does help minimize the amount of fabric in the corners.

That tip Laurie posted the link to works great. It was in my Singer sewing books from years ago and does help minimize the amount of fabric in the corners.