Toby Flood scored a first-half try for Newcastle
Newcastle (13) 16
Pens: Wilkinson (3)
Northampton (0) 7
Newcastle finally banished any worries about relegation with a win over Northampton which added to Saints' worries at the foot of the table.
Toby Flood scored the only try of the first half on seven minutes after which Saints had plenty of possession but could not find a way through to score.
Finally, Christian Labit scored for Northampton despite doubts as to whether he was in control of the ball.
Carlos Spencer converted but Jonny Wilkinson's boot made Newcastle safe.
The Falcons are now 12 points clear of Saints, who only have two games left to avoid relegation to National League One.
Two points adrift of Worcester at the bottom, they travel to face play-off chasing Wasps next Sunday, 15 April, before ending their campaign at home to London Irish on 28 April.
Worcester also face the Exiles in Reading next Sunday, with the Warriors' final game at home to Saracens.
Newcastle director of rugby John Fletcher:
"I suppose I'm happy. It lifts a bit of the stress and I suppose we can relax a bit and push on. It will be a good game against Gloucester.
"We looked nervous and lost our shape pretty quickly despite Toby Flood's early try which we should've built on.
"I don't envy the teams at the bottom - a good side will go down this season."
Northampton head coach Paul Grayson on their survival chances:
"We shouldn't beat ourselves up and we must put this behind us.
"It's not yet a lost cause, but it'll be tough. Next week we're at Wasps, then it's the Heineken Cup semi-final and we finish at home to London Irish.
"It was a great chance to put pressure on Worcester, but we were up against a side also fighting for their lives and you couldn't expect them to roll over."
Newcastle: Burke; May, Tait, Noon, Flood; Wilkinson Dickson; McDonnell, Thompson, Ward, Sorenson, Perry, Parling, Woods, Wilson.
Replacements: Golding, Long, Buist, Dowson, Rudd, Grindal, Crichton.
Northampton: Diggin; Lamont, Reihana (capt), Kydd, Cohen; Spencer, Robinson; Smith, Hartley, Budgen; Gerard, Short; Tupai, Fox, Labit.
Replacements: Cortese, Brooks, Browne, Hopley, Howard, Myler, Going.