Customers at a restaurant in the US are rallying to support a black waitress who received a racist handwritten note instead of a tip.

Restaurant server Kelly Carter, who works at Anita's New Mexico Style Cafe in Virginia, said the two white customers left a receipt after she had served them breakfast with the written message: "Great service don't tip black people."

She said the couple appeared to be in their mid-20s and had spent US$30 (S$43) on food.

Carter says there was no indication the couple were unhappy with her for any reason during the incident on Saturday (Jan 7).

Since then, however, customers have started requesting Carter as their server and some are even stopping by to give her hugs and money.

Restaurant owner Tommy Tellez told BBC News the response has been "phenomenal".

People have been dropping by the restaurant to give Ms Carter cash, Mr Tellez said, and a YouCaring campaign has raised over US$300 for her.

Her regular customers have been stopping at the eatery to give her hugs.

Tipping is customary in the US, where restaurant servers often earn less than the minimum wage, with tips supposed to make up the difference in pay, said the BBC.

Ms Carter told local media that one of the diners who left the note had even complimented the breakfast she served them.

She says that she would gladly serve the pair again, adding "one hateful remark cannot stop me" and that she would recognise them if they returned to Anita's.

"My arms are still opened to him," she said, offering to serve them again.

Anita's owner Mr Tellez said that Ms Carter has "handled it very well" and that he agrees with her desire to serve the pair again.

"Two wrongs don't make a right", he told the BBC, adding that the note was "appalling, disheartening, and outrageous".

He thinks political rhetoric from the 2016 presidential campaign means that "racism has certainly been on the table the last 18 months" and has thrown fuel on "a fire that has never gone out" in the US.

Ms Carter says she really does hope to see the couple again.

"Just me serving them will let them know they did not get the best of me. And I truly mean that."