After just two years, should I refinance again?

Q: Would it be an advantage to refinance a 15-year, $130,000 loan at 4.625% if I just refinanced two years ago? My house is worth $225,000, our credit score is 800, and I want to pay off our house before retirement.
What about closing costs, etc?

A: The answer is "maybe". You don't mention how many years you have until retirement, and you're already two years into your mortgage. Certainly, it's possible for you to lower the interest rate to perhaps 4% with a new 10-year loan, but since your interest differential will be small, your monthly payment will probably rise somewhat.