Most homeowners find that their escrow account simplifies budgeting, especially as they won't have to pay an entire year's tax bill or insurance premium at one time. In addition, your mortgage servicer will pay these bills on your behalf, so you won't have to watch your mail for these bills. This eliminates the risk of being charged additional fees for late payments.
After you've been in your home for a year, your mortgage servicer will conduct an annual escrow review or analysis. This review compares your escrow account's annual balance to your future annual taxes and insurance premiums. If these have become more expensive, your escrow payments may be increased to cover them. However, if your escrow analysis finds that you have surplus funds in your escrow account, you may receive a refund.
Source: Consumer Finance.gov