l am hearing a ticking noise and am worried it might be the timing belt.

Timing belts usually need changed by every 50k miles.
The ticking could be any number of things. If it ''ticks'' while sitting still, it could be from using low octane gas. It could be that you have some valve lifters that are loose. It could be your radiator fan is nicking the fan shroud or something close by.
It is hard to tell without more info, but those are some things you could check.

The timing belt is either working or not. If your timing belt was not working, then you'd know it because the engine would not run.

However, if there are a lot of miles on the car, it may be time to replace it anyway. the timing belt is a wearable item just like spark plugs, etc., so l would get it replaced after 70,xxx - 100xxx miles

Yes the 2.2l L and 2.5l GT motors are both interference, if the timing belt goes, you wo not be very happy. All subaru engines from 96+(maybe 97 can not remember) are interference engines.

The ticking is not the timing belt its the lifters . Subaru is are bad for lifters ticking. Yes they are an interference engine ( do not let someone tell you they are not just finish repairing one for the belt breaking and it bent 3 valves ) Replace the belt every 75000 km ( not sure of the mileage ) or 5 years whichever comes first. Doing the lifters and the belt at the same time could save you a couple of bucks. Good luck hope l helped
GM tech for 20 years

If it concerns you take it to a mechanic you trust who is familiar with Subaru. Is your engine a DOHC? If no, not to worry but the timing belt should be changed every 50-60,000 miles. Get it changed to be safe. Does the noise happen when the engine is cold? Does it dissipate after 20 or so minutes? The ticking you hear is probably piston slap due to the horizontal boxer engine.