The official color of Donald Trump's US-Mexico border wall is unknown as construction has yet to begin. However, there is speculation that the border wall will be painted beige, given the fact that Trump said, “Believe me, if it was a great wall, it would have been very easy to do. We have a lot of money in the country, but we don’t want to use it for the wall.”
Given Trump's comment about the wall needing to be visible for high visibility, beige is a popular color choice as it won't stand out considerably against the terrain of the environment.
The beige color could be a matte, flat or gesso beige and depending on the time of day and terrain, it has the potential to blend in among the environment. However, Trump could also plan to use a glossy finish to create a larger barrier.
Currently, no details have been officially released and it may be some time before the exact wall color is revealed.