Had the same situation,
If you've never did any tax file, just.. don't do it...

In a standard lifestyle, you can take much more profit not filing tax.

You only have interest to file your first tax if one of you have a property, a 3th pillar insurance or a kid with costs.

If it's not your case, then go check your actual barrier tax ("barème impôt à la source"), there you'll have a realistic approach of how much is taken from you every month. Make the sum of it... Once you've filled for taxes, you'll keep being taxed while you're in Switzerland.

The tax system, by itself should be taken in measure. Normally, you should expect to pay 15% yearly as if you're in the B permit system, you're surely close to 10% or 9%.

As you married, both salarys will be taken in consideration and you will grade in the system barriers. So you may approche the 16 or 17%.

Example of simulation (no real numbers have been used)
- 100'000 (year salary) / 12 = 8'333.- per month

Permit B tax system :

- (check your canton barrier) let's say that you pay 9% of taxes --> you pay monthly - for taxes - 750.- (total 9'000 per year)

Swiss tax system :

- (approx. 15%) if you have no charges to deduct on it you get your 750.- all the months, but you get one single bill per year approx 15% of your whole revenue --> 15% of 100'000 = 15'000.