Mobile phone company O2 has apologised after a woman received a parcel addressed to "Ms Jew Face".
Joan Jennings, who is not Jewish, was shocked when the package containing a free Sim card and letter arrived with the offensive comment.
The letter, received on Monday, was addressed: "Hi Jew".
The following day Mrs Jennings contacted BBC Three Counties radio and the incident was discussed on air.
She said: "I received a folder through the post with the correct postal address but it said 'Jew Face'. It started off saying 'Hi Jew' and then went on with a spiel of why they were sending this thing.
"At first I thought it was slightly amusing and then it made me quite cross really. You could say it was racist.
"I've never been a customer of this company and I won't be in the future."
Consumer affairs show presenter Jonathan Vernon-Smith said: "I'm just trying to think if there's any rational explanation."
An O2 spokeswoman apologised for any upset the incident had caused and said "strict filters" which remove offensive words or comments had not detected the problem.
She added: "We are reviewing our procedures with our suppliers to ensure this does not happen again."
It is thought the problem was most likely caused by someone mischievously adding Mrs Jennings' address to a mailing list with the false name.