Active leak or old scar?
Mark the edge of the stain lightly with a pencil and note the date. If the stain grows past your line after the next rain, the leak is active. If it stays put through a few storms, you're probably looking at the scar of a past problem (sometimes one a previous owner already fixed, sometimes one that's just waiting for the right storm).
Feel matters too. An active leak often leaves the drywall damp or soft after rain. Old stains are dry and firm. A moisture meter settles it definitively, and checking with one is part of any assessment we do.
Why the stain isn't below the hole
Water travels. It comes in upslope, rides rafters and the roof deck sideways and down, and drops where gravity finally wins. A stain near an interior wall can trace back to a chimney, a vent pipe, or a valley a surprising distance away.
That's also why a stain in a ceiling corner often points at flashing where the roof meets a wall or chimney, our number one leak source. (More on flashing leaks here.)
Not every ceiling stain is the roof
Before anyone climbs a ladder, it's worth knowing the impostors. Bathroom fans that vent into the attic instead of outside, sweating ducts, condensation from poor attic ventilation, and plumbing on the floor above all leave stains that look exactly like roof leaks.
A quick tell: stains that grow in cold snaps but ignore rainstorms usually point at condensation, not the roof. Stains that track with rain point up. Either way, the attic above the stain is where the answer lives.
What to do about it
If it's active: contain the water, photograph everything, and get it looked at soon. Our triage guide covers the tonight-versus-this-week decisions, and the Roof Leak Guide covers the whole journey from stain to fix.
If it's an old scar: get the roof checked before you repaint, not after. There's nothing quite like painting a ceiling twice. A free assessment tells you whether the underlying problem was ever actually fixed.