What happens if you miss the notice deadline for a break clause?

If you miss the notice deadline for a break clause, the right to break is lost for that break date. In most cases, you are then bound by the lease until the next break date (if there is one) or until the lease expires naturally at the end of the term -- which could be several years away at full contracted rent.

There is very little the courts can do to help. English property law has consistently held that break clause notice requirements are strict: the courts won't grant relief for a missed deadline, even where the failure was a clerical error or an honest oversight. This makes missed break clause notices one of the more expensive mistakes in commercial property -- particularly in rising markets where a tenant locked into below-market rent wants to leave, or in falling markets where a landlord locked a tenant in at a historic high rate.

The only fix after the fact is negotiating a surrender with the landlord, which means the landlord has leverage. A calendar reminder at the notice deadline -- not just the break date -- is the entire solution.