Obvious, the first reaction to this question would be – well, it depends on what job you have or what’s your outfit for that day in order to know how to match it with your boots.
Speaking in general, things are like that: the color of your boots is essential because it can ruin or highlight the value of your entire outfit.
If we are talking about a demanding job where you work directly with clients, then definitely the color should be black and it can be matched very easy with almost any outfit. But, because you depend on the colors your outfit already have, then you could also think about brown.
Here are some models of black boots:
And here are some models of brown boots:
In the situation in which you are a bold person and you love being into the trends, you could also try a pair of grey boots.
Colors are many and there are enough variants to get you problems. Important is to know that, the way you choose your boots and of course their color depends the success of your entire outfit.