With regard to services, and I am strictly speaking about customs related to the Jodo-Shu sect of Buddhism here in Hawaii, there are services held on the 7th day, 25th day, 49th day, 100th day and successive years - 1, 3, 7, 13, 17, 23, 25, 27, 33, 37, 43, 47, and finally, the 50th year when the soul has achieved enlightenment - Nirvana. Since a person is deemed 1 year old at birth (gestation), the deceased is considered a year older at death, and service years are actually less 1, so for example the 50th anniversary service is actually held on the 49th anniversary of the death.

Since it may be difficult to keep track of the service anniversaries, a lot of families make arrangements with a local Buddhist temple to perform services for the deceased on the anniversary date.