How long does a commercial EPC take?
Updated 23 October 2026 · SEO Dons Editorial
What are the steps in getting a commercial EPC?
A commercial EPC is a short chain of steps, and the building sets the pace of most of them. The government's guide says that once an assessor is commissioned there are three main steps: gathering information about the building, analysing it to identify its zones, and entering it into approved software. Booking comes before those steps. Checks and lodgement come after them.
| Step | What happens | What sets the pace |
|---|---|---|
| 1. Commission and book | A request goes to an assessor accredited for your building's category, with the information and payment, or undertaking to pay, that is usually needed. GOV.UK says to check that the assessor is part of an accredited scheme. | How complete the request is, how many quotes you compare and when the assessor can attend. |
| 2. Survey | The assessor gathers zones and dimensions, activities, heating and ventilation, lighting and fabric details. Even where detailed plans exist, they must validate the information with a site inspection. | Floor area, the number of zones and services, access to plant and occupied space, and whether up-to-date plans exist. |
| 3. Model | The data goes into approved software: SBEM, or a dynamic simulation model (DSM) where SBEM may not be sophisticated enough to assess the building accurately. | The assessment level. For level four and five buildings the assessor must also visit, inspect and record where the data came from. |
| 4. Quality checks | Accreditation schemes must provide for consistent and accurate assessments, and the register applies validation rules when data is lodged. | Mostly outside the owner's control. Accurate, documented inputs help. |
| 5. Lodge and issue | The assessor enters the data on the register before giving the certificate to the person who asked for it. Lodging generates the certificate reference number. | An EPC and its recommendation report are only valid once lodged. |
What makes the process quicker or slower?
No government guidance gives a timescale for the assessment itself, so the answer depends on the building and the assessor. These are the factors the guidance points to.
- Information to hand. The guide says up-to-date information and plans make the process less time-consuming, and that without plans the assessor must survey the building and gather the information. The lists in what you need to get a commercial EPC quote and how to prepare your building cover what to collect.
- Access. Regulation 45 puts a duty on everyone with an interest in, or in occupation of, the building to allow the access an assessor reasonably needs. Agree dates with occupiers early.
- Size and complexity. More zones and services mean more to record and check. For level four and five buildings the assessor must visit, inspect and keep a record of where the data came from.
- Assessor availability. The government's consultation response records differing views. Accreditation schemes and some assessors thought capacity was sufficient for a pre-marketing EPC not to slow marketing, while other assessors cited practical challenges such as assessors being on leave. Asking more than one assessor is sensible.
- An existing certificate. Regulation 7 applies only where no valid EPC is available. If a valid one exists, the guide says it can be provided to any prospective buyer or tenant, so checking the register first can remove the wait.
What does the law say about timing when you sell or let?
The legal clock starts on the day a building is first put on the market, not on the day the assessor visits. Before then the EPC must be commissioned. After it, the seller or landlord and any agent must use all reasonable efforts to obtain a valid EPC in a 7-day period, with a further 21 days if that proves impossible despite those efforts.
This is regulation 7 of the Energy Performance of Buildings (England and Wales) Regulations 2012, which applies where a building is to be sold or rented out and no valid EPC is available. A building is put on the market when the fact that it is or may become available is first made public, with the intention of marketing it. An EPC is commissioned when a request is properly addressed to an assessor accredited for the building's category, in the form and with the information and payment, or undertaking to pay, usually needed.
- Before marketing: commission the EPC. Any agent must be satisfied that it has been commissioned.
- Day 1: the building is first put on the market.
- Days 1 to 7: use all reasonable efforts to obtain a valid EPC.
- Days 8 to 28: if that failed despite those efforts, obtain it in these further 21 days.
As a hypothetical illustration of how the periods count, if a unit were first advertised on 1 June, the 7-day period would end on 7 June and the further 21 days on 28 June.
Regulation 6 runs alongside this. The EPC must be made available to a prospective buyer or tenant at the earliest opportunity, and no later than when written information about the building is first given or a viewing happens. That is a reason to commission early even though the 28 days exist.
The guide, last updated in December 2017, explains why 7 days is workable: "Evidence shows that most EPCs are obtained within 3 days so this should not be a challenge in most cases." That is its reasoning for the legal deadline, written about most EPCs. It is not a timescale for your building. The penalties and defences for missing the marketing rules are in can you sell or let a commercial property without an EPC.
Will the timing rules change?
The government says it intends to. In its partial response to the consultation on reforming the Energy Performance of Buildings regime, it states: "We intend to update regulations so an EPC is required at the point of marketing a property rather than the point of sale or rent". The response describes the current regulations as allowing up to 28 days following marketing for an EPC to be obtained.
That is an intention, not law. The response says a further response on the remaining parts of the consultation will be published in 2026, and on 22 October 2026 legislation.gov.uk listed no outstanding effects on the 2012 Regulations, so the 7-day and 21-day periods in regulation 7 stand. This site's guide to commercial EPC changes separates what is confirmed from what is proposed.
An owner expecting to market soon can plan for both: check the register, commission early and aim to hold a valid EPC before the first advert goes out. That suits today's rule and should suit the intended one.
How can an owner plan the timing?
- Work back from the date the EPC is needed, such as the first advert or the start of a letting.
- Search the register for an existing certificate. A valid EPC lasts 10 years unless a newer one replaces it, as how long a commercial EPC is valid explains.
- Gather the building details an assessor needs to scope the job.
- Line up access, plant rooms and occupiers before the visit.
- Check that the assessor is accredited for your building's category before relying on the booking for a marketing deadline.
With the details together, you can request quotes for a commercial EPC through the site's form. Each assessor then confirms the level and what the job involves, which is when a realistic timetable becomes clear.
Sources
- The Energy Performance of Buildings (England and Wales) Regulations 2012, regulation 7, legislation.gov.uk, checked 22 October 2026
- The same Regulations, regulations 6, 22, 27 and 45, and the table of contents, legislation.gov.uk, checked 22 October 2026
- A guide to Energy Performance Certificates for the construction, sale and let of non-dwellings, Ministry of Housing, Communities and Local Government (GOV.UK), updated 11 December 2017, checked 22 October 2026
- Get a new energy certificate, GOV.UK, checked 22 October 2026
- Reforms to the Energy Performance of Buildings regime: partial government response, Ministry of Housing, Communities and Local Government and Department for Energy Security and Net Zero (GOV.UK), updated 9 March 2026, checked 22 October 2026
- Reforms to the Energy Performance of Buildings regime: consultation outcome, GOV.UK, updated 9 March 2026, checked 22 October 2026
- Energy Performance of Buildings Certificates in England and Wales: technical notes, Ministry of Housing, Communities and Local Government (GOV.UK), updated 30 July 2026, checked 22 October 2026
Common questions
Does the legal clock start when I book the assessor?
No. The 7-day period starts on the day the building is first put on the market. Booking matters because the EPC must already have been commissioned by then, and a request counts only if it goes to an assessor accredited for the building's category.
Can an EPC be produced without a site visit?
Not for an existing commercial building. The guide says the assessor must validate the information with a site inspection even where plans exist, and for level four and five buildings must visit and inspect every building they certify. It also says remote lodgement, lodging data the assessor has not collected or verified, is not acceptable.
Is the certificate usable as soon as the modelling is finished?
No. The EPC and its recommendation report are only valid once lodged on the central register, which generates the certificate reference number every valid EPC must carry. The assessor must enter the data on the register before giving the certificate to the person who requested it.