Data released by NHS England has shown some practices could lose up to £7.41 per patient per year if they are minimum practice income guarantee (MPIG) outliers.
Practices are identified as outliers if they heavily reel on MPIG to bolster practice finances.
In total, 98 practices have been designated 'outliers'. Over the next seven years, a practice with 6,000 patients could face losses of more than £311,000.
Changes in the 2013/14 GP contract mean that MPIG top-ups to core pay will be redistributed over the seven years from 2014.
Most practices will benefit from the redistribution of finances, but some could be hit hard.
The list of outliers is "only a guide for area teams", the NHS England document states.
The document reads: "There may be practices outside the list of 98 "outliers" for whom other commissioning arrangements may be appropriate."
NHS England issued advice to area teams at the end of December on how to deal with outliers. The guidance suggested smaller practices could be merged, federated, made more efficient through cost cutting, or that other contracting and commissioning solutions could be found.
Although there have been concerns that practices in rural areas could be worst-hit by the cuts, only 15% of outliers were rural practices, while 18% of all practices are in rural areas.