This seemed as good a place as any to put this.

I have a looooong torso. Any bra I wear rides up, no matter how I adjust the straps, and ends up cutting into my boob. This is at least partly because they aren't very big yet, so they don't do much for holding the bra cups in place. But I think it's also because it's such a long way from my nipples to my shoulders .

Any advice for keeping bras from riding up?

Fitting by a specialist bra shop should help find a brand that suits you.  It may take trying on a few.
I wear small inserts and have found the German Amoena brand is the only one I am really comfortable with. They also make Breast forms, mainly for mastectomy patients.
German sizings are apparently a little larger than most, and actually suit Australian physiques well. Including transwomen. 
Hope you find one that fits properly, it is so much better.

Karen.

My La Senza sports bras are the only ones that don't ride up (much). Which is weird, because they're the least adjustable ones. Shame La Senza went bust (no pun intended, but what the hell, let's go with it...)

M&S is on reflection not the best place to go, because they only sell their own bras. I probably need to go to a Big City to find a specialist bra shop.

In the end, what turns out to fit best is a size too small, with strap extenders. My boobs are just too small for their correct size of A cup. I may look into AAs if I can find a good source.

I found I started to need extenders on my last bra, so there has been an increase in cup size, from an AA to closer to A.  A specialist is worth looking for as there are a few tricks to getting a good fit.
It all means shopping, and even dykes love that!  Bra means new knickers, so might as well have a new outfit , so new shoes etc. 
Love the new hair colour.
Karen.

Yeah, I looked after posting and La Senza UK isn't dead, they're just 'building a new website' after going into administration. I think they got bought out by one of the big sports traders.

If the ride up its mostly to large band size ,assuming you can adjust the straps so to are way to loose.
Extenders can ruin much as the move the attach points of the straps,you could tryout on a old worn bra to move the straps attachment with a safety pin. Also a long line or wide band bra help to hold things more in place.

QuoteAny bra I wear rides up

mmm try a strapless  impossible to ride up !
As with all textile its made to *fit* on a average person

Funnily enough, I've just found the perfect bra - Sloggi Double Comfort Crop Tops - sort of a soft sports bra, it has a broad comfort band under the boobs, and so far isn't going anywhere I don't want it to, and is pretty supportive. Also, cotton - and not too pricey. I've just ordered a few more, this is now my bra of choice . I hope this image isn't too risqué - it's not me!

 I have the same problem, except my reason for wearing a bra is to make it look like I have breasts in the first place. There isn't enough tissue to keep the cups down, so I would have to wear a sports bra... but if I did that, I might as well just go braless for all the good it would do.

I just discretely pull my bra down when it becomes an issue. Looking like I have As is worth it - if I went with a sports bra, I doubt I'd make it to a AA.

Once you fill those cups with at least an A cup breast-tissue it will stop riding up. It's pretty obvious what happens.
Breasts sag... brassieres pull them back up... nothing much in there, the bra rides up... :-)

YMMV,
Axélle

 Yeah, well, not everyone gets that far without a BA...

Sure, it's obvious what the problem is, but some of us just have to deal with it until we get a BA, and this thread was to help make that easier.

Bleeeh.

...and some of us aren't interested in a BA. I'm happy with my Sloggi bras now.