A policy lapses when there isn't enough value left to cover the monthly charges and the grace period runs out. Usually that's 31 days, sometimes 61, and it starts from a notice the carrier is required to send. Once it's over, the coverage is gone.
Most contracts include a reinstatement provision, commonly three to five years from the lapse date. Inside that window you can apply to bring the same policy back rather than buying a new one. And the reason to care is that a new policy would be priced at your current age and current health.
What reinstatement costs: all the back premiums, plus interest on them, often around 6%. On a policy lapsed two years at $9,000 a year, that's $18,000 plus roughly $1,600 of interest, due at once. Some carriers will let you reinstate at a reduced face amount instead, which lowers the catch-up. Ask, because it isn't always offered.
You also have to prove insurability again. That's a fresh application, often a paramedical exam, and full underwriting. A health event during the lapse period is the reason most reinstatements get declined, and it's frequently the same health event that made the premium hard to pay in the first place. The sequence is common enough to plan around.
Two things restart that people don't expect. The contestability period generally starts over from the reinstatement date. The carrier gets a fresh two years to investigate a claim. The suicide exclusion typically restarts too. What doesn't restart is the surrender charge schedule or the policy's original issue age. That's the whole reason reinstating beats replacing.
Any loan that was outstanding comes back with the policy, and it comes back with the interest that accrued while the policy was lapsed. That's often the number that makes people walk away.
Before it gets that far, there are cheaper exits. A reduced paid-up election converts what's there into a smaller policy with no more premiums due. Extended term uses the cash value to buy term coverage for a set number of years. An automatic premium loan provision, if the policy has one and it's active, borrows against cash value to pay the premium without asking you. Any of those beats a lapse, and all of them have to be elected before the grace period closes.
If a policy has already lapsed, call the carrier and ask for the reinstatement deadline in writing. That date is the only thing that matters, and people assume it has passed when it hasn't.