Two of the division's form sides came together at Brunton Park on Saturday afternoon as Cheltenham made the trip up the M5/M6 corridor.
United were unbeaten at their own base in the league and were looking to become the first League Two team since Wycombe Wanderers in 2006 to win their first six consecutive home league fixtures.
With Josh Kayode away on intenational duty with Ireland it meant one change to the starting eleven from the Newport game, with Omari Patrick drafted in.
It was an end-to-end start to the game with the Robins immediately on the front-foot with a long throw from Tozer. Hayden was up to meet it as Chapman lurked.
The resulting corner was well dealt with at the front stick, but May had waited deep and he volleyed instinctively as it came his way. McDonald stood tall to make the block.
Up at the Waterworks End and a run of corners came United's way as the visitors struggled to deal with the Guy deliveries. Raglan got in the way at the back post and he had his heart in his mouth as Mellish looked to finish it off. The ball wouldn't quite settle and the clearance was made.
A cross on the run from May had Williams interested for Cheltenham as he angled a sprint into the box, but he couldn't get there and Farman watched it behind.
The visitors had a good spell, but they were almost undone when a corner came to nothing and the Blues broke in numbers. Tanner clipped a deft pass for Patrick to chase but Blair lunged in to make a vital tackle.
Reilly then had an effort stopped at source as Carlisle stayed forward, but they were rocked on the quarter hour when a long throw from Tozer was met on the jump by Will Boyle. His close-range header had venom and it arrowed into the back of the net.
The game settled into a pattern as the visitors protected their lead, but United weren't too far away when Guy popped another good delivery into the mix. Hayden and McDonald moved to get a touch but Raglan marshalled it away.
Another good period followed for the Blues and Reilly put Flinders under pressure when a long ball forward from Farman skipped off the surface. The clearance had to be rushed, and Alessandra took charge of the long throw that followed. A scuff from Hussey allowed Patrick to shoot, but it rose quickly and it flew over the target.
But disaster struck at the home end when an inswinging set piece delivery caused problems. Mellish appeared to be barged off the ball but there were suddenly loud appeals for a penalty when Ben Tozer fell to the ground. The referee pointed at the spot and Conor Thomas sent Farman the wrong way as he found the back of the net from 12-yards.
United looked to rally straight away with crosses pinging into the box fron left and right. And they got the reward for their endeavours deep into time added for the first period when Patrick pulled wide. He spotted the run from the predatory Jon Mellish, and the midfielder made it 11 goals in 11 games with the neatest of finishes.
The Cumbrians came out of the second half blocks at pace and Guy kept the back four busy with more teasing crosses and passes. He used Tanner as a bounce board to mount a right wing attack and his outswinging clip was begging to be put away.
A cushioned trap on the chest from Patrick then brought Riley into play, and he lost his marker with a clever twist and turn. His shot took a deflection and Flinders stooped low to gather.
There was still danger for the hosts and May reminded them of that when he found unexpected space. He thought he'd made it through but McDonald was there to block.
Farman had to push a dipper from the same player away moments later when a rasping drive threatened to creep below the bar.
Both sides kept looking for the next goal, and the ever-dangerous May tried his luck on the run as he angled in from the touchline. It was a decent connection but it whipped the wrong side of the upright.
Striker Omari Patrick put an instinctive attempt just past the angle of post and bar as United continued to probe, but the threat from the launched Tozer missiles refused to go away. Boyle will feel he should have scored when a Raglan flick from one such throw landed at his boot just a yard out. He somehow conspired to send it high.
It became very tight through the closing stages but the Cumbrians should have pulled level as the clock ticked down. A half clearance from a Guy cross eventually came to Anderton, and his miscued effort bobbled through legs to find Reilly. He suddenly had just Flinders to beat, but the keeper spread himself to make a fantastic point-blank save.
That was it for chances as the Robins saw the game out to bring an end to United's impressive home run.
Carlisle United - Mellish (45)
Cheltenham Town - Boyle (15), Thomas (36 pen)
Carlisle United - Farman, Tanner, Hayden, McDonald, Anderton (c), Riley (Obiero 74), Guy, Mellish, Alessandra (Bennett 84), Reilly, Patrick. Subs - Dewhurst (gk), Devine, Hunt, Charters, Malley.
Cheltenham Town - Flinders, Hussey, Tozer (c), Raglan, Thomas, May (Lloyd 84), Blair, Williams, Boyle, Sercombe, Chapman. Subs - Harris (gk), Clements, Reid, Addai, Freestone, Sang.
Referee - Andy Haines
Assistant Referee 1 - Mark Cunliffe
Assistant Referee 2 - Matthew Parry
Fourth Official - Samuel Barrott
Attendance - BCD