Straps that slide off the shoulder
Short answer: Straps slide when they are too loose or when your shoulders slope. Tighten them, choose a style with straps set closer in, or use a strap clip.
The two common causes
Either the straps are adjusted too long, or you have sloping shoulders where there is nothing to hold against. The first takes a minute to fix, the second needs a different cut.
Choose the cut to suit the shoulder
With sloping shoulders, choose styles where the straps sit closer to the neck, meaning a racer back, a crossed back or wide straps. Wide straps slide less than narrow ones because there is more friction. See bamboo tops for women.
The quick fix
A small strap clip gathers the straps at the back and solves the problem on every top. It costs almost nothing and moves between garments. A safety pin does the same job but wears on the fabric.
When the bra is at fault
If the band is too loose, all the weight rests on the straps and they get tightened beyond what they can take. Tighten the band first and see whether the straps then stay put. See bamboo bras without underwire and bamboo slips.
Frequently asked questions
Does tightening the straps all the way help
Rarely. Straps that are too tight cut into the skin without solving the real problem.
Are there straps that slide less
Yes. Wide straps and straps with a silicone edge on the inside stay in place better.
Can straps be sewn down
Yes, a couple of stitches in the shoulder of a top will hold a bra strap in place.