Asking early is not the same as falling behind
You need a bit more time on a deadline. But asking for it feels like admitting you are behind, so you either stay silent and rush, or you over apologise and sound flustered.
The secret is to tie the ask to quality and to be specific. Vague requests sound like excuses. Specific ones sound like planning.
Three lines that ask with confidence
“I want to do this properly, so can I get until Thursday?” ties the extra time to a better result, which is hard to argue with.
“Realistically, I can have a solid version by Friday” shows you have actually thought about it. Offering a partial now, such as a rough draft tomorrow, reassures the other person that things are moving.
Why it works
People do not lose trust when you ask for time. They lose trust when work is late with no warning.
A clear, specific request made early is a sign of someone who manages their work well, and it almost always gets a yes.