New Jersey planned to originally hold its primary elections on June 2, 2020, the same day as that of Montana, New Mexico, South Dakota and the District of Columbia,[2] and was the only state on that date to move its primary, as New Jersey is traditionally one of the last states to vote.

New Jersey Governor Phil Murphy announced on April 8, 2020, that, because of the COVID-19 pandemic, the primary would be postponed until July 7.

In the semi-closed primary, candidates had to meet a threshold of 15 percent at the delegate district or statewide level in order to be considered viable.

The 126 pledged delegates to the 2020 Democratic National Convention were allocated proportionally on the basis of the results of the primary.

A limited number of polling stations in each county was available on primary day for those who preferred to vote in person (including with provisional ballots if they were unable to obtain one) and for voters with disabilities.