A transfer has three costs: a deposit fee, a conversion fee and a send fee. Grey shows all three, and the naira amount your recipient receives, before you confirm. That makes the rate only one part of what a USD to NGN transfer really costs.
On a $500 transfer funded by ACH, the deposit fee is 0.8 percent (minimum $2, maximum $10), about $4. The conversion fee is 1 percent, capped at $6, so $5 here. The send fee is shown separately, and the exact naira amount for a USD to NGN transfer is shown before you confirm. Grey supports transfers to GTBank, Access Bank, Zenith Bank, UBA, First Bank and all major Nigerian banks via NIBSS. Your recipient does not need a Grey account.