UKH

I'm buying a friend a harness but she is tiny and looks like only a small childs harness will fit but these don't look very comfortable or that good.

Is there anyone else in the same situation or knows of a ladies XS harness that sizes up small?

There are a huge range of kids harnesses that don't look any less comfortable to me than an adult one. You will have more luck finding a few kids ones to try on than such a small adult one.

My daughter (150cm) has tried pretty much every harness. She uses the DMM tomcat, it is very comfortable the only issues is that it has only two gear loops so not great for trad.

https://dmmclimbing.com/Products/Harnesses/Tomcat

The Venture in XS is small enough around the waist but the leg loops are slightly too big

https://dmmclimbing.com/Products/Harnesses/Venture. 

My Eldest  daughter found the Petzl Macchu kids harness (21.3"-25.2" waist 13.4"-17.3" leg loops)  comfortable before she was large enough to fit a Petzl Luna in XS ( 25.5"-27.9" waist 18.1"-22" leg loops)

My middle daughter found the rise too low on the Macchu but the Luna in XS is too big, so she has always used the DMM centre harness at the wall, she has tried on a Beal Venus (24"-29.9" waist 17.7"-22.4" leg loops)which she found a good fit.

Do you know your friends thigh and waist measurements?

My GF had similar issues and couldn't find anything that fit correctly. She ended up with a Climbing Technology Anthea harness in a small/medium and it could be fitted tighter still if required.

Well padded with 4 generous gear loops and a smaller 5th loop round the back. Its made for an ideal Trad harness.

Thanks for the tips, will look into them all. It's a Christmas present so asking for leg measurements might be a give away. Only for indoors so not bothered about gear loops. Will buy from somewhere with a good returns policy!

Sorry to not be helpful, but you are not going to find a reputable seller that will let you return a harness. Would you buy a harness knowing that it might be returned?

Can you buy a voucher and take her along​for a fitting? I really wouldn't recommend buying a harness without trying it on anyway.

Don’t buy a harness without her trying them on.  

Hello

Like other posters have mentioned, definitely don't buy a harness without your friend trying it on first. 

I'm 5'1", fairly trim and usually wear XS or S harnesses - sizing isn't totally consistent across manufacturers, but I've generally found Arcteryx FL-355, Petzl Luna, Wild Country Mission and Black Diamond Technician XS harnesses to be on the small side. Comfort and fit will depend on your friend's body shape and measurements, have a think as well about whether she will be using the harness much outdoors. I mainly climb trad, so I like having a fifth gear loop, which all of the above harnesses have (the one on the Arcteryx harness is very small but I've been able to carry a full rack comfortably). The fifth gear loop is important on XS harnesses if your friend climbs trad as the main gear loops will be smaller than on larger harness sizes and therefore carry less gear.

Hope this helps.