It depends. If you value convenience, then you might prefer using your current lender. You'll already know how the company works and be familiar with its customer service operations. However, just because a lender offered the best rate or lowest fees when you got your initial mortgage doesn't necessarily mean it will offer the best deal when you refinance. Your financial situation also may have changed since you got your first mortgage. For example, if your credit score has dropped, then you may need to find a lender that has a lower minimum credit score.