An airport security deadline 20 years in the making is a month away — and authorities are urging the public to take it seriously.

After years of delays, the Transportation Security Administration will begin enforcing the Real ID rule May 7. Travelers who fly domestically will need to provide a compliant license or acceptable alternative when they go through security checkpoints.

“I do anticipate some disruption,” said Rich Davis, senior security adviser at risk mitigation company International SOS. “I think it’s going to be a little bit of a stressful day or 10.”

According to federal documents, about 56 percent of identification credentials in circulation complied with the standards as of January 2024. TSA spokeswoman Lisa Farbstein said last week that 80 percent of travelers have been going through security checkpoints with Real IDs or approved alternatives; between 2 and 3 million people go through TSA on most days.

Here’s what travelers need to know: