That's what I did and I recommend if you can!
When I bought the house I live in 2008, the mortgage rate was above 6% if I remember right. I refinanced in 2016 when I snapped 3.625% interest rate. A smaller principal amount and the lower interest rate contributed to a lower monthly payment.
It was great! 4 years later, I did refinance again. This time I reduced the mortgage from 30 years to 15 years to lower the interest rate. Now my interest rate is 2.875%. Though I need to pay more each month now, it does make sense to me since I don't anticipate working for ever!!! Yes, I am thinking of retirement. If I don't need to pay for mortgage when I retire, it will be such a relief.
Are you thinking of refinancing? Check it out. The rates are so far so good!