Air taxi Captain reported a safety concern when ATC cleared the flight to an intersection that was similar sounding but slightly different spelling; in the same airspace; which resulted in the flight turning off course. The crew corrected the spelling of the intersection and proceeded to the correct navigation fix.

Narrative

We were operating a 135 flight from BED to ZZZ on Day 0. On this leg I was the pilot flying and my co-Captain was the pilot monitoring (PM). During climb out ATC gave us a reroute (Direct Jersy Q75 ZZZ ZZZ1 direct) and cleared us up to FL400. My co-Captain put the first fix in as Jerzy and we went direct. It was straight ahead and seemed to be the appropriate distance. However; he was having issues connecting Q75 from Jerzy to ZZZ. I looked down and said to try it as Jersy and ZZZ was then able to connect and then we went direct to Jersy. At this time ATC gave us an amended clearance to stop the climb I believe at FL390 and said it appeared we were drifting south and he was seeing our current turn to the correct fix of Jersy and then recleared us up to FL400. Seperation was not lost and no deviations were noted on altitude. We informed him of the spelling error and nothing else was said from the controller. On the initial reroute the controller did give the correct spellings for the fixes and my co-Captain wrote it down as Jerzy. It just happens that these two fixes are only about 25 miles apart with being in similar directions when coming from the northeast. Jerzy is just slightly south with Jersy being slightly north. Either fix would appear to be in the appropriate direction. We only knew the difference because Q75 would not join up off of Jerzy.Suggestions: These two fixes that sound exactly the same are in extreme close proximity to each other and have similar looking letters; Z and S. These two fixes can be easily mixed up. I would recommend changing one of the names.