Do not confuse waiting time with eligibility.cimple said:
Each province has their own rules.
Waiting time says how fast you can get your health care coverage after moving. Many provinces have no waiting time if you are moving from outside Canada. Ontario has a 3 month waiting time. BC has 2 months plus the balance of the third. Quebec has a 3 month waiting time but pregnancy and childbirth are exempt.
Eligibility is how long you must live in the province in order to keep your health care. This is usually at least 6 months a year. Ontario has an additional rule where they state you must live in the province at least 5 months in your first 6 in order to be eligible.
It is therefore possible that you gain a health card, either by moving to a province where you get it right away or by waiting your 3 months but then losing your eligibility because you did not stay in the province. It has even happened in BC that the province decided that a woman who did her waiting period, got health care, had a baby and then left was retroactively deemed not to have been eligible for health care because she did not stay for 6 months in her first year and she was given a bill for all of the expenses they paid for her. Therefore, it is not a good idea to move somewhere just to get first day health care and then move to another province right away. In order to avoid trouble, be honest, apply for health care only if you are staying and let the health care know if you move.