A back-end load is a mutual fund fee assessed upon redemption.
Funds with back-end loads are sometimes called "B" shares. These funds impose a contingent deferred sales charge, or CDSC, which is paid at the time of redemption. This fee is generally much higher than a front-end load.
The good news is that it declines incrementally to zero over time and usually disappears in five to eight years.
These funds charge 12b-1 fees, which are typically higher than for front-end-load funds. These funds may also convert "B" shares into "A" shares after the load period has expired.