Can I use 185 65r15 tires on my 2013 Ford Fiesta?

Can I use 185 65r15 tires on my 2013 Ford Fiesta? - 1

Nope.

Depends on what wheels are fitted to it not what the car is.

The stock tires (base model) are 185/60/R15. With 185/65/15 the width with be the same but the diameter of the tire will be about 0.8 inch taller. Which is a moderate change. Chances are they'll fit without issue, but your speedometer/odometer will read a little slow, and the effective gearing will change, giving you a bit less acceleration, with reduced city fuel economy, but slightly better highway fuel economy.

As you may know 185/60R15 is the OEM tire size for your 2013 Fiesta. Your suggested tire size of 185/65R15 has a slightly taller sidewall. Not much but just enough that you would more than likely have decreased stability and handling capability. Your speedometer would also be slightly out of calibration. It's doable to use the taller tire but certainly not recommended.