How Long Does COBRA Coverage Last? 18, 29, and 36-Month Rules

When people ask how long COBRA lasts, the most common answer is 18 months. That's correct for most situations — but it's not the complete picture. Federal COBRA actually has three duration tiers depending on who was affected, what triggered the coverage, and whether certain conditions are met after enrollment.

Here's how each tier works, and which one applies to you.

Tier 1: 18 Months — The Standard Duration

The default COBRA duration is 18 months. This applies when the qualifying event is:

• Voluntary or involuntary termination of employment (other than gross misconduct)
• Reduction in hours causing loss of coverage

The 18-month clock starts on the date your employer coverage ended — not the date you elected COBRA, not the date your notice was sent. So if your coverage ended May 31, your 18-month period runs through approximately November 30 of the following year, regardless of when you actually elected.

This is by far the most common COBRA situation. If you're reading this because you were laid off or had your hours reduced, this is almost certainly your tier.

Tier 2: 29 Months — The Disability Extension

If a qualified beneficiary in your family is determined to be disabled by the Social Security Administration within the first 60 days of COBRA coverage, all qualified beneficiaries in the family can extend coverage from 18 to 29 months.

The requirements are specific:

• The disability must be determined by the Social Security Administration — not a private disability insurer or a doctor's letter
• The disability determination must be made within the first 60 days of COBRA coverage
• You must notify the plan administrator within 60 days of the SSA determination and before the original 18-month period ends
• The disability must continue through at least the 18th month of coverage

During months 19 through 29 of coverage, the plan is permitted to charge up to 150% of the full group premium (rather than the usual 102%). That's a meaningful price increase, but still usually cheaper than comparable individual disability coverage.

The 11 extra months of coverage can be critical for someone transitioning from COBRA to Medicare disability (there's a 24-month waiting period after Social Security Disability Insurance begins) or awaiting a disability determination that takes longer than expected.

Tier 3: 36 Months — Family Qualifying Events

For qualified beneficiaries other than the covered employee — spouses and dependent children — certain qualifying events trigger 36 months of coverage:

• Death of the covered employee
• Divorce or legal separation from the covered employee
• A dependent child aging out of coverage (typically at age 26)
• The covered employee becoming entitled to Medicare

These events primarily affect family members rather than the employee themselves. A spouse who loses coverage due to divorce, for example, gets 36 months rather than 18.

The rationale: these events typically leave the affected person with fewer alternatives than a terminated employee (who often finds new employment with new coverage within a year or two). Three years gives divorcing spouses and aging-out children more runway to secure alternative coverage.

Second Qualifying Event Extension

A less common but meaningful extension: if a second qualifying event occurs during the initial 18-month COBRA period, the affected spouse and dependent children may extend their coverage to 36 months total from the original qualifying event.

Example: A husband is laid off in March and elects COBRA for himself and his wife. In November (month 8 of COBRA), the couple divorces. The divorce is a second qualifying event. The wife's COBRA coverage can now extend to 36 months from the original March qualifying event — effectively giving her an additional 18 months.

To get this extension, the qualified beneficiary must notify the plan administrator of the second qualifying event, usually within 60 days.

When COBRA Can End Early

Your coverage duration is a maximum, not a guarantee. COBRA can end early in specific circumstances:

• Non-payment of premium. Miss a premium deadline (including the grace period, typically 30 days) and coverage terminates permanently — not suspended, terminated.
• The employer stops providing any group health plan. If your former employer eliminates its group health plan entirely, COBRA rights end.
• You become covered under another group health plan. Starting a new job with health coverage generally terminates COBRA — though there are nuances if the new plan has a pre-existing condition exclusion.
• You become entitled to Medicare. Medicare entitlement can end or limit COBRA coverage for the individual, though it may trigger extended coverage for covered family members (see Tier 3 above).
• Voluntary termination. You can drop COBRA at any time.

What Happens When COBRA Ends

When your COBRA period ends — whether at 18, 29, or 36 months — the end of that coverage is itself a qualifying life event for the ACA marketplace. You get a Special Enrollment Period, usually 60 days, to enroll in a marketplace plan without waiting for Open Enrollment.

This is worth planning for. Don't let COBRA end without a replacement plan lined up. Start shopping the marketplace 60-90 days before your COBRA end date so the transition is seamless.

The Bottom Line

• Standard COBRA duration: 18 months (termination or hour reduction)
• Disability extension: 29 months (SSA-determined disability in first 60 days)
• Family qualifying events: 36 months (death, divorce, aging out, Medicare entitlement)
• Second qualifying event can extend initial 18-month periods to 36 months
• Premium can increase to 150% during disability-extension months
• COBRA ends early for non-payment, new employer coverage, Medicare, or voluntary drop
• End of COBRA triggers a Special Enrollment Period for marketplace coverage

Check your COBRA Election Notice for the specific duration that applies to your situation. The cover letter or coverage summary will state your exact end date — not just "18 months," but an actual calendar date.