[1] Derived from the author's own childhood growing up living in poverty and with a mentally ill parent, The King of Jam Sandwiches is for Eric Walters "the most important book he's ever written" and "certainly the most personal."

The King of Jam Sandwiches won the 2020 Governor General’s Literary Award for Young People's Literature – Text.

Deborah Dundas of the Toronto Star writes, "He provides an intimate and hopeful perspective and a glimpse into a world we rarely see closely enough to understand.

"[2] In the weekly Canadian Review of Materials, Teresa Iaizz from the Toronto Public Library finds it, "written in a nonjudgmental and compassionate way", "allows children to better understand a very serious topic.

"[4] Amanda Toth at the School Library Journal writes, "Highly recommended for most middle grade sections.