Void Periods — How to Calculate and Reduce the Cost

Updated March 2026 · 7 min read

A void period is any time your rental property sits empty and generates no income. Even a few weeks between tenancies can cost hundreds or thousands of pounds in lost rent — while your mortgage, insurance, council tax, and utilities continue regardless. Understanding void periods, how to calculate their cost, and how to reduce them is one of the most practical skills a landlord can develop.

What Counts as a Void Period?

A void period begins when a tenancy ends and the property is empty. It ends when a new tenancy starts and you receive the first month's rent. This includes:

• The gap between one tenancy ending and another beginning
• Time taken to carry out repairs or refurbishment between tenants
• Time spent finding new tenants if no tenant is waiting
• Any period where a property sits uninhabited while you decide what to do with it

Note: some landlords define "effective void" as any period where they have fixed costs but no income. Others count only the gap between tenancies. Both are valid — what matters is being consistent in your calculations.

Average Void Periods by Region

The English Private Landlord Survey and letting agent data consistently show that average void periods vary by region and property type. In high-demand areas, voids can be as short as a few days. In lower-demand areas or for larger properties, they can extend to weeks.

The national average across England is typically cited at around 3 weeks per year, but this masks wide variation. If you are buying in a specific area, talk to local letting agents about current tenant demand and average time-to-let before factoring void assumptions into your yield calculations.

How to Calculate the True Cost of a Void

The cost of a void is more than just lost rent. During a void period you typically continue to pay:

• Mortgage interest — this does not stop because the property is empty
• Council tax — landlords become liable for council tax on empty properties (often at the full rate)
• Utilities — if utilities are in your name during the void
• Buildings insurance — continues regardless
• Letting agent re-let fee — if using an agent, there is typically a fee to find a new tenant

To calculate the annualised cost of a void allowance, use this formula:

Worked Example

Property: two-bedroom flat in Sheffield. Monthly rent: £800. Assuming a 3-week annual void:

• Weekly rent equivalent: £800 ÷ 4.33 = £184.76/week
• Lost rent over 3 weeks: £554
• Additional costs during void (council tax, utilities, re-let fee): approximately £350
• Total annual void cost: approximately £904

As a percentage of annual gross rent (£9,600): this void reduces effective income by 9.4%. This is why prudent investors build a 5–10% void allowance into their net yield calculations.

Strategies to Reduce Void Periods

1. Market the Property Before the Tenancy Ends

Do not wait for a tenant to leave before advertising. Give notice with enough time to list the property, take viewings, and have a new tenancy ready to start within days of the old one ending. Most letting agents will market a property with 6–8 weeks' notice.

2. Price Competitively

Overpriced properties sit empty longer. Research comparable rents in your area monthly, not annually. The rental market can move quickly, and being 5–10% above market can mean 3–4 extra weeks void that costs more than the premium rent ever would have generated.

3. Maintain the Property Well

Well-maintained properties let faster and retain tenants longer. Responding promptly to maintenance requests, keeping communal areas clean, and refreshing décor between tenancies all reduce re-let time and improve tenant retention — which eliminates voids entirely.

4. Target Long-Term Tenants

Professionals and families tend to stay longer than students or young singles. Longer tenancies mean fewer void periods. Accepting pets (with appropriate clauses in the tenancy agreement) is a well-evidenced way to attract tenants who plan to stay — pet-owning tenants have fewer options and are more likely to renew.

5. Consider Rent-to-Rent or Serviced Accommodation

For properties in the right locations, letting to a serviced accommodation operator on a guaranteed rent arrangement eliminates voids entirely. You receive a fixed monthly amount regardless of occupancy. The trade-off is that you receive below-market rent and have less control over your property.

6. Use a Good Letting Agent

A well-connected local letting agent will have prospective tenants on a waiting list and can often reduce time-to-let significantly. The management fee is a cost, but faster re-letting and lower voids can more than compensate for it, particularly for landlords with multiple properties.

Void Periods and Your Yield Calculation

Always factor void periods into your net yield calculation before purchasing a property. A 6% gross yield property with 4 weeks of annual voids has an effective rent of approximately 92% of the advertised figure — reducing the effective gross yield to around 5.5% before any other costs are considered.

Use our yield calculator to model void costs alongside management fees, maintenance, and mortgage payments to get a realistic net yield figure.

Key Takeaways

• The national average void period is approximately 3 weeks per year, but varies significantly by location and property type
• The true cost of voids includes lost rent plus ongoing fixed costs (council tax, mortgage, insurance)
• Budget a 5–10% void allowance in net yield calculations
• Market properties before tenancies end, price competitively, and maintain well to minimise voids
• Longer-term tenants eliminate voids — prioritising tenant retention is often the best strategy