Bal grout

[d noulton]

mapei white grout compares to a used nappy crap other colours are fine
though to be fair its hard to find a pure white

 

[jay]

construction chemicals Kemgrout 501 white

 

[ms.tiles]

hi

Ask if they have a split bag out back that you can grab some from you might be lucky.
I always use ardex grouts or mapei as you can get the silicone to match if using a colour.
For white grout i buy a 10kg bag of white bal grout and some GT1 additive from Topps if i need it flexible. The true colour always comes out when its dry and grout is always darker when wet.

hope this helps