Walt Disney World and Disneyland are increasing the prices of single-day tickets at certain times of the year and setting expiration dates on tickets in hopes of preventing overcrowding during the theme parks’ busiest times, company officials said Saturday.

The single-day ticket prices are either staying the same or are increasing no more than $5 under the new price structure that went into effect Sunday. Last year, Disney rolled out a pricing plan that allows visitors to view a calendar from eight to 11 months out to determine which days are considered “value,” “regular” or “peak” times. Visitors pay more on “peak” days, the busiest times as forecast by park officials.

Disney is raising prices after a 5 percent decline in attendance at its U.S. theme parks during its most recent quarter, which included the holiday season.

The goal of the varied price structure is to give visitors an incentive to go during times when the parks aren’t crowded, officials said. There have been times during the holidays and spring break when the crowds have been so large that Disney has had to stop selling tickets.

“Our pricing provides guests a range of options that allow us to better manage demand to maximize the guest experience and is reflective of the distinctly Disney offerings at all of our parks,” said Disney spokesman Jacquee Wahler.

After the price increase, “value” days for Magic Kingdom in Florida cost $101 for children ages 3-9 and $107 for visitors who are 10 or older, a $2 increase. During “regular” time, park visitors will pay $5 more, after prices jumped to $109 for young children and $115 for others. The “peak” prices remained the same, at $118 for young children and $124 for others.

At Disneyland, prices for single-day tickets increased by $2 to $5. The regular price of admission at the Anaheim, Calif., park rose to $110 for visitors older than 9, up from $105. A ticket during peak periods climbed to $124 from $119. And the value ticket’s new cost is $97, up from $95.

All tickets will now have expiration dates. In the past, only one-day and Florida resident tickets had expiration dates. Also, guests will be able to save $20 on multiday tickets when they purchase them in advance.