American reporters who wear wrinkled, ill-fitting clothes had better dress to impress — if they want to get near William and Kate when they come to the US next month.

To prepare for Prince William and Duchess Kate’s visit to New York City and Washington, DC, in December, the British monarchy laid out a dress code for style-challenged scribes, Politico reported.

“Journalists … should comply with the dress code on formal occasions out of respect for the guests of The Queen, or any other member of the Royal Family,” the British monarchy website declares.

“Those wearing jeans or trainers will not be admitted and casually dressed members of the media will be turned away. This also applies to technicians,” the warning notes.

It then offers a handful of snobby fashion tips.

“Smart attire for men includes the wearing of a jacket and tie, and for women a trouser or skirt suit,” it proclaims.

The Duke and Duchess of Cambridge will visit New York on Dec. 7 — so clean up your act, you haggard writers.