Relegated Fulham ended their Premier League campaign with another defeat.
An easing of Covid-19 restrictions meant 2,000 Whites fans were able to see the game at Craven Cottage.
But it was another disappointing display by the Whites, whose season was summed up by Ivan Cavaleiro missing a golden chance to equalise when he blasted over the bar.
Joe Willock put Newcastle ahead by scoring for the seventh game in a row.
He ran with the ball from near the halfway line and then took advantage of a ricochet by firing into the net.
Newcastle sealed their win with a late penalty by Fabian Schär after Kenny Tete had fouled Matt Ritchie.