How much should it cost to get a crack in my exhaust welded?

Where is the crack?

In the exhaust manifold?

Or in a pipe?

Or the muffler?

-Engine overhaul mechanic and general automotive mechanic since 1972

I would guess maybe $15-$20 to have a muffler shop weld it.

Depends. Will a shop do that? Where is the crack? It may be cheaper to cut off a section & replace it. Or, it may not. How would we know unless we saw it?

1/2 hour labor. Maybe $50.00.

If the exhaust is rusted and too thin, welding it won't do any good. You can't weld rust. If the pipe is still structurally sound, I would guess maybe $15-$20 to have a muffler shop weld it.

The problem with welding a crack is that it often gets worse when an attempt is made to weld it. The ends need to be drilled at the ends of the cracks to stop the crack from growing when the attempt to weld it is done. To get it done right would require that the manifold be removed from the car,  repaired (braze would be better) and reinstalled. This means the labor for replacing the manifold has been done. Welding is not cheap in my neck of the woods and the minimum charge is for one hours work.

If you can get in around it I strongly recommend products that bond to the manifold and set by heat to fix the problem short term:

https://www.oreillyauto.com/shop/b/exhaust-parts-1...

$70 an hour plus parts.  Muffler shops are remove and replace places.  Not many will do temporary repairs.

I BET it wouldn't cost more to replace the cracked exhaust pipe than to repair it.

In the UK we can repair such cracks cheaply and easily with 'exhaust bandage' kits. The repair passes our MOT test. Find out if your tester will accept such a repair before you shell out on welding.

Less than $500.  Why don't you call a muffler shop where you live and ask them directly?