What. is lowest kidney function can get before dialysis is required?

GFR 10: This differs for everyone but in a relatively narrow range. Some patients with cardiac disease benefit from dialysis at higher GFR (low creatinine), african americans seem to tolerate higher creatinine without symptoms. In general convert the creatinine to egfr (online calculator) and expect dialysis at egfr less than 15 ml/min.

It depends: Usually when kidney function is less than 20% doctors start discussing about dialysis.Typically dialysis is started when kidney function is less than 10%. However if symptoms occur earlier, some start when kidney function is less than 15%