Before you start

California residence
Income information for subsidy or Medi-Cal eligibility
An SSN or ITIN for the marketplace application
A qualifying life event, if enrolling outside the annual open-enrolment window

Step-by-step

1
Enrol in your employer's plan within the new-hire window
Typically 30 days from your start date, and missing it can mean waiting for the next open enrolment. Compare the deductible and out-of-pocket maximum, not just the premium.
Via employerWho: YouFirst 30 days of employment
2
Check Medi-Cal eligibility first
California expanded Medi-Cal well beyond the federal minimum, and in 2024 extended full-scope coverage to income-eligible adults regardless of immigration status. The state's 2025 budget made changes to new adult enrolment and to premiums from later years, so confirm the current position with the Department of Health Care Services rather than relying on an older article. Medi-Cal enrols year-round.
OnlineWho: You
3
Without an employer plan, use Covered California — not HealthCare.gov
California runs a state-based exchange with its own enrolment calendar, which has historically extended past the federal deadline, and its own state subsidies layered on the federal ones. Going to the federal site sends you back.
OnlineWho: You
4
Understand the state individual mandate
California kept an individual mandate after the federal penalty went to zero. Going without minimum essential coverage for a substantial part of the year triggers a penalty on your California return unless you qualify for an exemption. It is administered by the Franchise Tax Board, not by the marketplace, and people who assume the federal repeal ended it get caught at filing.
OnlineWho: You
5
Decide about Kaiser deliberately
Kaiser Permanente is both the insurer and the provider — its own hospitals, its own doctors, its own records. It is efficient and widely liked and it is a closed system: you get care inside Kaiser or you pay out of pocket. That is a bigger decision than picking between PPO networks, and switching later requires a qualifying life event.
OnlineWho: You
6
Register with a primary care physician in month one
Do it while you are well. An established relationship is what gets you referrals and urgent slots later, and confirming the practice is in your network before the first visit avoids an out-of-network bill for a routine appointment.
In personWho: YouMonth 1
7
Plan for wildfire smoke season
Late summer and autumn can bring days of hazardous air quality from fires elsewhere in the state, occasionally for a week at a time. A decent air purifier and N95 masks are ordinary household items here, and people with asthma or young children should have both before the season rather than during it.
In personWho: You

Documents you’ll need

Proof of California residence
Income documentation for subsidies or Medi-Cal
SSN or ITIN
Immigration documents for marketplace eligibility categories
Evidence of losing prior coverage, if using a special enrolment period

Things most newcomers don’t know

California still has an individual mandate, and it is enforced through the state tax return.

The federal penalty went to zero in 2019 and most people assume mandates ended everywhere. California, Massachusetts, New Jersey, Rhode Island, Vermont and DC kept theirs. In California it is assessed by the Franchise Tax Board when you file, and a newcomer who arrives mid-year uninsured can owe it without ever having heard of it.

Source: California Franchise Tax Board

Covered California layers state subsidies on top of the federal ones.

California funds its own additional premium assistance and cost-sharing support beyond the federal subsidies, which means the same income can produce a materially different net premium here than in a federal-marketplace state. It also means the federal calculators understate what you would actually pay. Use the state exchange's estimator.

Source: Covered California

Choosing Kaiser is choosing a hospital system, not a network.

Kaiser Permanente insures and delivers care in one integrated organisation. Inside it, coordination and records are excellent and costs are predictable. Outside it, you are self-paying. If you have an existing specialist relationship you want to keep, or a condition managed elsewhere, work out the answer before enrolment rather than in March.

Source: community-reported

Medi-Cal's rules on immigration status have moved twice in three years.

California extended full-scope Medi-Cal to income-eligible adults regardless of immigration status in 2024, and the 2025 state budget changed the terms for new adult enrolment and added premiums from later years. This is one of the fastest-moving eligibility questions in the country. Anything written more than a year ago is likely to be wrong in one direction or the other — check with the Department of Health Care Services directly.

Source: California Department of Health Care Services

Common mistakes to avoid

Going to HealthCare.gov instead of Covered California and losing time.
Assuming no coverage means no penalty, when California still levies one.
Missing the 30-day new-hire enrolment window at a new employer.
Enrolling in Kaiser without realising it is a closed system.
Relying on year-old information about Medi-Cal eligibility, which has changed twice.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.