"Sweetest Sin" received positive reviews from critics, with some calling it a catchy tune and an "ode to booty knocking".

[3] The recording process of "Sweetest Sin" was documented in an episode of Simpson's reality series, Newlyweds: Nick and Jessica.

[4] Simpson originally recorded "Sweetest Sin" confidentially in a slightly remixed form and announced she was pleased with its progress.

[5] Sal Cinquemani of Slant Magazine said, "[Sweetest Sin], the catchy tune, penned by Diane Warren, is a glossy, ever-so-slightly over-produced affair.

The video continues with intercut footage of the previous scenes, until the final seconds of the song, when Simpson is joined by her husband, in which they move on their bed on the beach.

[13] Simpson performed "Sweetest Sin" live at the Trump Taj Mahal in Atlantic City, New Jersey.