Trying to check his benefit balance, he got through to a sex line instead.
In an unfortunate misprint on some cards, the number to report lost and stolen cards put callers through to a live chat line.
The Maine Department of Health and Human Services said it was aware the number was wrong by one digit.
When LJ Langelier, 25, called the number before taking his son shopping,  a recorded voice gave him an unexpected invitation: "Welcome to America's hottest talk line. Ladies, to talk with interesting and exciting guys free, press one now."
"It played over my car speaker, I was like, 'Wow, I must have messed that number up somehow really bad'," he told the Bangor Daily news. "I look at the card, I dial it the exact same way again, and it keeps happening. I thought it was just hilarious."
When he checked with friends, they turned out to have the same misprint.
In its defence, the human services department says the company that operates the sex line searches for phone numbers that are very similar to widely published government phone numbers and buys them to take advantage of consumers misdialling.
It said the number was being corrected on all new cards.
An unsuspecting father in the US state of Maine got a shock when he dialled the phone number on the back of his electronic benefit transfer card.