By the time the clocks go forward and everyone's coats get lighter, I find myself reaching past the black bag on the hook without even thinking about it. Tan does something a black bag never quite manages in spring and summer light, it looks warm rather than official, like you've dressed on purpose rather than just left the house.
It's the bag for the in between occasions, the ones that aren't smart enough for a structured handbag and not casual enough for a canvas tote. A lunch that might turn into drinks, a wedding in a field, a weekend away where you need one bag to do everything from the train to the second day's brunch. It softens up a work outfit without making you look like you're trying to escape the office, and it's forgiving on the sort of day that starts at a desk and ends somewhere you didn't plan to be.
In terms of what it actually sits next to in a normal week, tan is unexpectedly easy around colour. It doesn't fight with navy, it calms down anything too bright, and it sits next to denim like it was always meant to. I wear mine with a lot of white and cream through summer and it reads clean rather than beige on beige, which I was worried about the first time I tried it. Gold hardware tends to look richer against it than silver does, though I've got one with silver clasps that I still reach for, so don't let that stop you.
On finish, go for something with a bit of grain or texture rather than a glassy, flat tan, because the flat ones show every scratch and water mark within about a fortnight, and I say that having ruined one in a car park puddle I swore I'd walked round. A mid tan rather than a very orange or very pale biscuit shade is the easiest to live with, it works against black, grey, denim and most prints without anyone clocking that it's doing any heavy lifting at all.
If you've got no tan bag at all and you're starting from nothing, go for a cross body or a short shoulder bag in that mid tan, with a strap long enough to sit across the body properly and a shape structured enough to hold itself up when it's half empty. Avoid anything with a stiff handle only, your shoulder will hate you by the afternoon. Tomorrow morning I'd put it with wide leg jeans, a plain white shirt and the sort of trainers that have gone slightly grey at the toe from actual wear, and call that sorted before I've had coffee.