Compare interest rates for the best overall earnings

Look for the best regular – not introductory – interest rate. An introductory interest rate is usually not the same as the regular rate, which kicks in a couple of months later, and you'll be earning at the regular rate for a much longer time.

I recommend: Bankrate.com is a great place to find the best rates at specific banks. Enter your state, city, and type of MMA, and violá – you have a side-by-side comparison of local bank MMA offerings with introductory and regular interest rates, and more. At Interest.com, input your info, choose "MMA", and compare rates near you.

Check out minimum requirements

MMAs usually require higher minimum balances and/or higher minimum initial deposits than savings accounts do. Find the right account with requirements your business can meet to avoid penalties. .

I recommend: Capital One's Business Money Markethas no fees or minimum balance requirements – in fact, you don't even have to visit a bank to open your account! At Netbank, you can open a small business MMA with $1,000, with no minimum balance requirements after the initial deposit.

Choose special features

The features of an MMA vary, so find out specifics before applying for your account. Many business MMAs allow checking account overdraft protection using the MMA funds, special "deposit only" cards, and the ability to tie your line of credit to the MMA.

I recommend: Visit Bank of America to learn about their Business Investment Account (MMA), which was designed to complement your business checking account. This MMA offers a business deposit card so your employees can make deposits (but not withdrawals, as with an ATM card).

Find FDIC-insured institutions

Regardless of the interest rate offered, if a bank's accounts are not insured by the Federal Department Insurance Corporation (FDIC) - which guarantees checking/savings accounts in member banks up to $100,000 per depositor – then your money isn't safe.

I recommend: Check out FDIC-insured Wachovia, which offers a Money Market "Sweeps" account. Each day, excess balances in $1,000 increments, above a target amount, are "swept" from your business checking account into your business MMA.