What size needle to use?

Hi everyone!

I’m knitting a garter stitch afghan, using 6mm circular needles. It’s 350 stitches across, and it’s going to end up about 80"+ wide and 60"+ long. (Why yes, there may have been a bit of underestimation when I planned it out, why do you ask? :mrgreen:)

Now that I’m almost 2/3 done, I’ve realized that I’m not sure what size needle I should have on hand to cast off with. I usually get it wrong with scarves, so… suggestions would be greatly appreciated!


I think it would all depend on whether or not you plan on doing anything with the border. I’ve knit a ton of afghans and I usually crochet a border on it, just because I like that sort of thing. Others leave theirs unadorned.

A lot depends on you. some people use the same needle for casting off and have no issues. If your cast off is tight and seems to pull in the cast off edge, you can use a needle 1, 2 or even 3 sizes bigger to cast off with.

Hi, thanks for the replies!

I’m definitely not doing anything with the border. I [I]wish[/I] I could crochet! I would [B]love[/B] to make a wave afghan. But 6 books later, and I still can’t manage to make a 3" x 2" square without it twisting :frowning: I think I’ll need someone to teach me in person.

I can also tell you that I can’t use the same size needle to cast off – I’m definitely not that good! I’ve tried 1 and 2 sizes larger on smaller pieces, but I never made a notation on what I thought of each of them, and it was so long ago I’ve plum forgotten all the details… I’m a little horrified that it’s so dependant on the individual knitter – I was hoping for a nice standard procedure, lol.

Well, maybe you could tell me: Of the people who do like to use a larger size needle to cast off, do more people go 1 or 2 sizes up? My tension is pretty even, so that shouldn’t be a factor.

I’d just hate to ruin this piece after working on it for probably a year, by the time it’s done. Do you think I would get a good enough idea if I knitted a long strip (like a scarf knitted sideways) to test out the different results? If so, what dimensions do you think would be big enough?

Thanks so much again, guys!


I go up 3 or 4 sizes larger if I think it’ll look good that way, and I’m not a tight knitter. There’s a really loose bind off that’s easy and you can usually use the same size needles. Knit 1, put it back on the left needle, then k2tog tbl, put the new st back on the left, k2tog tbl and keep repeating across. It sounds harder than it is, but you might want to practice it on some other yarn first.