RICS Relativity Tables: How They Affect Your Extension Cost

Understand how RICS relativity tables work, which tables are most cited in First-tier Tribunal decisions, and why a small difference in your relativity percentage means thousands of pounds.

What Are Relativity Tables?

Relativity tables are mathematical schedules that express the value of a leasehold interest as a percentage of the equivalent freehold value, at different remaining lease lengths. They are a fundamental tool in all leasehold enfranchisement premium calculations and are published by major surveying firms including Gerald Eve and Savills.

Why Relativity Matters

The relativity percentage directly affects both the reversion value and marriage value components of the premium. A seemingly small difference can significantly alter the total figure — which is why disputes between surveyors often focus on which relativity table to use and what it yields for a specific lease length.

Typical Relativity Values (Approximate)

• 100 or more years: 99.0% | 90 years: 98.5% | 80 years: 97.0%
• 70 years: 95.0% | 60 years: 91–92% | 50 years: 87–88%
• 40 years: 81–82% | 30 years: 73–74% | 20 years: 62–63%
• 10 years: 43–45%

A difference of just 2% in the relativity applied to a £400,000 property represents an £8,000 difference in the marriage value component alone — highlighting why specialist surveyors are essential, not optional.

Which Table Is Most Authoritative?

No single table has been prescribed by law. The most commonly cited in Tribunal decisions are the Gerald Eve and Savills tables. The First-tier Tribunal typically takes a weighted average or selects the table with the most relevant local comparables.

The No-Act World Distinction

Standard tables apply to statutory lease extensions. Where a leaseholder is negotiating informally or is not yet eligible for the statutory route, different relativity figures may apply — reflecting the market value of the short lease without the benefit of enfranchisement rights. This distinction can substantially affect premiums.