UK Workers Can Claim Unfair Dismissal After Six Months From January, and the Award Has No Ceiling

For two decades, US employers with a UK team have leaned on a quiet assumption: if a hire is not working out, there is a long runway to act before the legal stakes rise. That runway ends on January 1. From that date, almost anyone who has been on the payroll for half a year can claim unfair dismissal, and if they win, there is no longer a statutory ceiling on what they can recover. The change does not make dismissals illegal. It makes casual ones expensive.

What Changes, and When

The government's updated Employment Rights Act timeline, revised on September 25, confirms the sequence. Day-one statutory sick pay and day-one paternity leave took effect on April 6, 2026. On October 1, the time limit for bringing an Employment Tribunal claim rose from three months to six. On January 1, 2027, the qualifying period for unfair dismissal falls to six months for dismissals from that date, alongside the removal of the cap on compensatory awards.

The reach is wider than most managers assume. Protection applies at the date of dismissal, not the date of hire, so anyone with six months' service on January 1 is covered immediately. According to Mishcon de Reya, July 1, 2026 was the last hiring date that would put an employee over the line on day one, and roughly 6.3 million employees currently have between six months' and two years' service. The government expects around 9,000 additional Acas cases and about 3,000 additional tribunal claims each year.

Why "Dismiss Before Six Months" Is Not a Safe Plan

The obvious workaround is to make every hard decision inside the first six months. Mishcon de Reya warns that the arithmetic is tighter than it looks. Once an employee has worked for a month, they are entitled to at least one week of statutory notice. If an employer dismisses without giving that notice, the qualifying period is measured from the date the notice would have expired. A dismissal at five months and three weeks can therefore land on the wrong side of the line. The firm's advice is to reach decisions by the five-month mark and to cap probation at five months, including any extension.

The government has also dropped a proposed statutory probation period that would have offered a lighter dismissal process for new hires, so there is no special procedure to fall back on. After six months, an employer needs a fair reason and a fair process, which means documented concerns, a chance to improve, a hearing, and an appeal. That is a manager capability problem as much as a legal one, because the paper trail is created, or not created, in ordinary one-to-ones long before HR is involved.

The Number That Changes the Risk Math

Removing the cap matters more than the shorter qualifying period for senior roles. DLA Piper notes that compensatory awards were previously limited to the lower of 52 weeks' pay or £118,223. In its worked example, a 50-year-old sales manager earning £79,114 would have been capped at about £80,000, but could claim more than £500,000 once lost earnings through to retirement are counted. The firm also points out how unusual this makes the UK: most European jurisdictions keep statutory caps, and only Luxembourg currently runs a fully uncapped unfair dismissal regime.

Employers have noticed, but not uniformly. An Acas survey conducted by YouGov of 1,050 senior decision makers found 23% expect the new unfair dismissal protections to be among the hardest changes to adopt, behind day-one sick pay at 30% and day-one paternity leave at 27%. Acas Chair Baroness Maggie Jones called the Act "the biggest shake-up to employment law in a generation." For US-headquartered companies running UK staff from a distance, the risk is that probation norms set in another country quietly carry over, with nobody local who owns the calendar.

A Playbook for the Next Twelve Weeks

• Pull a UK service-date report now. Identify everyone who will pass six months' service in the first half of 2027, and every open performance concern attached to those names, so nothing drifts past the line by default.
• Shorten probation to five months or less. Rewrite UK offer letters and contracts so probation, including any extension, ends before the qualifying date with room left for statutory notice.
• Schedule structured review points. Build formal check-ins at months two, three, and four, with written outcomes, so a decision at month five rests on a documented record rather than a feeling.
• Train the managers who actually run probation. First-time and remote managers are the most likely to avoid hard conversations, and under the new rules an undocumented concern is effectively an unraised one.
• Reprice dismissal risk for senior UK roles. Share uncapped exposure scenarios with finance and legal, and revisit settlement agreement practice now that a tribunal award has no statutory ceiling.
• Resist the contractor reflex. Converting UK roles to contractor arrangements to dodge the new rules invites employment status challenges, so any change in engagement model needs a genuine classification review first.

The January change will not punish employers that already manage performance well. It will expose the ones that relied on a two-year buffer instead of a process. For HR teams with a UK footprint, the work between now and New Year is less about legal interpretation and more about making sure every manager knows the clock is now six months, not twenty-four.