Replacing a ceiling light is usually not a huge project, at least when everything behind the ceiling is in decent shape. In most homes, the total cost ends up somewhere between 150 and 400 dollars, including the new fixture and the labor to install it.
If you are simply swapping out an old light for a new one and the wiring is already there, the process is fairly straightforward. An electrician removes the existing fixture, checks that the ceiling box is secure, connects the wires for the new light, and mounts it in place. For that kind of job, labor often falls in the 100 to 250 dollar range depending on where you live.
The price starts to climb when the situation is less simple. High ceilings can require more time and special equipment. Heavier fixtures may need a ceiling box that is rated to hold the weight. In older homes, wiring sometimes needs minor updates before a new light can be installed safely.
Then there is the fixture itself. A basic flush mount might cost under 100 dollars. A larger or more decorative ceiling light can run several hundred.
If the wiring is solid and the ceiling box is secure, replacing a light is usually manageable. If structural or electrical issues show up, the total cost can increase quickly. Getting a quote ahead of time is always a good idea.