Mr Sandford was dramatically arrested during a Las Vegas rally for Mr Trump.
He was accused of grabbing a policeman’s gun at a rally in Las Vegas in order to shoot at the candidate.
His mother says “he is remorseful over what he did”.
Lynne Sandford, from Dorking in Surrey, had previously said her son suffers from autism and should be allowed to return to the UK to carry out his sentence.
She said that after the election he feared what his punishment would be after learning that Mr Trump had won.
“Michael is afraid that because Donald Trump is now president-elect, it may have some bearing on the judge’s sentencing,” she told the Express newspaper before sentencing.
“He fears Donald Trump may intervene and choose to make an example of him.”
Sandford had faced up to 10 years in prison over the alleged assassination plot.
-BBC