Theme park tickets are free for children under 3-years old. And to answer your question, you do not need to make theme park reservations for a child of this age either.

In 2026, the policy at Disneyland Resort remains that children under the age of 3 do not need a park reservation or a ticket for entry. Disney defines a "Guest" for ticketing and reservation purposes as anyone aged 3 and older. Therefore, if your baby has not yet reached their third birthday, they are considered a "Guest of Mickey" and can enter the parks freely with a validly admitted adult. However, once a child turns 3, they must have both a valid theme park ticket and a corresponding park reservation for every day of their visit. It is important to note that while the baby doesn't need a park reservation, you should still include them in any dining reservations you make via the Disneyland app to ensure the restaurant allocates a table with enough space for a highchair or stroller. Families traveling in 2026 are also encouraged to utilize the "Baby Care Centers" located in both parks for a quiet space to feed and change their little ones.