Multi-site carbon reporting is the process of measuring and consolidating greenhouse gas emissions across multiple business locations into a single organisational footprint. Under PPN 06/21, UK organisations must report emissions for all operational sites in one Carbon Reduction Plan.
Multi-site carbon reporting introduces complexity that single-site businesses never encounter. When your organisation operates from two, five, or fifty locations, you must collect consistent data from each site, handle different energy suppliers, and aggregate everything into one coherent footprint that meets procurement requirements.
According to the UK Government's PPN 06/21 guidance, organisations bidding for contracts valued at £5 million or more must submit a Carbon Reduction Plan that covers their entire operational footprint. This means every office, warehouse, depot, and retail unit under your operational control must be included. There is no exemption for small or low-emission sites. The UK Government spends approximately £300 billion annually on procurement, and multi-site businesses represent a significant proportion of suppliers competing for these contracts.
The challenge is not just data collection. Different sites may have different energy suppliers, different billing cycles, and different operational patterns. A warehouse running 24/7 has a fundamentally different emissions profile from a small regional office open five days a week. According to the GHG Protocol Corporate Standard, organisations must apply a consistent methodology across all sites to ensure comparability and accuracy. This means establishing standardised data collection processes, training site managers on what data to capture, and building systems that can aggregate heterogeneous inputs into a single, auditable footprint.
Of the UK's 5.5 million SMBs, a substantial number operate from multiple premises. For these businesses, the gap between understanding that they need a Carbon Reduction Plan and actually producing one that consolidates all their sites is where most projects stall. The methodology itself is well established, but the practical implementation across multiple locations, each with their own data quirks, requires careful planning.
Before collecting any data, you must decide which consolidation approach to use. The GHG Protocol defines two primary methods: operational control and equity share. Most UK businesses bidding for government contracts use operational control, and this is the approach PPN 06/21 implicitly expects.
Under the operational control approach, you report 100% of emissions from every site where your organisation has the authority to introduce and implement operating policies. According to the GHG Protocol Corporate Standard, this means if you lease an office but control the heating, lighting, and day-to-day operations, those emissions fall within your boundary. If a landlord controls the building's energy systems and you simply occupy space in a serviced office, you may not have operational control over those Scope 1 and 2 emissions, though they would still appear as Scope 3 upstream leased assets.
The equity share approach, by contrast, reports emissions proportional to your ownership stake. This is more common in complex corporate structures with joint ventures and partial ownership. For most multi-site SMBs, operational control is simpler, more intuitive, and aligns with how procurement teams expect to see your data. According to DEFRA's environmental reporting guidelines, the operational control approach is recommended for most organisations as it reflects the emissions you can directly influence and reduce.
Choosing the wrong approach can lead to significant errors. If you operate a franchise model where individual franchisees control their own sites, those sites may fall outside your operational control boundary. Conversely, if you own and manage all locations directly, every site must be included regardless of size. Document your chosen approach clearly in your CRP methodology section so procurement evaluators understand your organisational boundary.
Different sites often use different energy suppliers, and this creates practical challenges for data collection. However, it does not affect the emission factors you use. According to DEFRA's 2024 UK Government conversion factors, you apply the same grid electricity emission factor regardless of which supplier provides your power.
The reason is that DEFRA's emission factors reflect the average carbon intensity of the UK electricity grid, not the specific fuel mix of any individual supplier. Even if one site purchases a "green tariff" or "100% renewable" electricity contract, the standard approach under PPN 06/21 is to use the DEFRA grid average factor. This is because market-based reporting, where you would account for renewable energy certificates, is not required by PPN 06/21 and could actually complicate your submission if procurement evaluators are unfamiliar with the methodology.
For gas and other fuels, the emission factors are based on the fuel type, not the supplier. Natural gas has the same emission factor whether supplied by British Gas, Octopus Energy, or any other provider. The practical challenge is simply collecting consumption data from multiple suppliers in different formats and billing cycles. Some suppliers provide monthly readings, others quarterly. Some report in kWh, others in cubic metres for gas. Standardise all data into kWh before applying DEFRA conversion factors to ensure consistency across your sites.
Where sites have different billing periods that do not align with your reporting year, you will need to pro-rate consumption. If your reporting year runs January to December but a site's gas bill covers November to January, you must estimate the proportion of that consumption falling within your reporting period. According to the GHG Protocol, reasonable estimation methods are acceptable provided they are documented and applied consistently. For more detail on emission factors, see our guide on consolidating emissions across locations.
Consolidation follows a clear hierarchy: collect site-level data, apply emission factors, calculate site-level totals, then aggregate into one organisational figure. The process must be documented in your CRP so that procurement teams and auditors can trace any number back to its source.
Start by listing every operational site with its type, size, and operational hours. For each site, collect consumption data for electricity, natural gas, other fuels, company vehicles, refrigerants, and any other relevant Scope 1 and 2 sources. According to the GHG Protocol Corporate Standard, Scope 1 covers direct emissions from owned or controlled sources, while Scope 2 covers indirect emissions from purchased electricity, heat, or steam.
Apply DEFRA 2024 emission factors to each consumption figure. For electricity, multiply kWh consumed by the grid electricity factor (currently 0.20707 kg CO2e per kWh for 2024). For natural gas, multiply kWh by the natural gas factor (0.18254 kg CO2e per kWh). Sum the results for each site to get site-level Scope 1 and Scope 2 totals, then sum all site-level totals to get your organisational figures.
For Scope 3, the same principle applies but the data sources are more varied. Business travel, employee commuting, purchased goods, and waste disposal must all be aggregated across sites. Some Scope 3 categories may be easier to collect centrally, such as business travel booked through a single agency, while others like waste disposal may need site-level data. The key is consistency: if you include waste data for one site, you must include it for all sites where waste is a material emission source. Document which Scope 3 categories you include in your CRP and ensure the methodology is applied uniformly across locations, following the approach outlined in our methodology page.
The most frequent error is double-counting emissions when sites share resources. If two offices in the same building share a gas boiler, you must allocate consumption between them rather than each claiming the full amount. According to the GHG Protocol, allocation should be based on a reasonable physical metric such as floor area, headcount, or metered usage.
Another common mistake is inconsistent reporting boundaries. If you include employee commuting for your head office but omit it for regional branches, your footprint is incomplete and potentially misleading. Procurement teams evaluating CRPs for contracts valued at £5 million or more will look for consistency across the entire organisation. An incomplete or inconsistent CRP can result in disqualification from the bidding process.
Failing to account for sites that opened or closed during the reporting year is another pitfall. If you acquired a new site in June, you should report six months of emissions for that site, not a full year. Similarly, if you closed a site in March, only three months of data should be included. Your CRP should clearly note any changes to your site portfolio during the reporting period and explain how this affects year-on-year comparisons.
Finally, many organisations underestimate the importance of documentation. Your CRP must include enough methodological detail that a third party could reproduce your calculations. This means stating which DEFRA emission factors you used, how you handled estimated data, what consolidation approach you applied, and how you allocated shared resources. Without this documentation, your CRP lacks the credibility that procurement evaluators expect.
CarbonPass Business plan is designed specifically for organisations with multiple locations. Rather than building complex spreadsheets that break when you add a new site, CarbonPass provides a structured workflow that guides you through data collection for each location and automatically consolidates everything into one organisational footprint.
You enter energy consumption data for each site separately, choosing from electricity, natural gas, company vehicles, and other emission sources. CarbonPass applies the correct DEFRA 2024 emission factors automatically, so you never need to look up conversion factors or worry about using outdated figures. Each site's emissions are calculated independently and then aggregated into your total Scope 1, 2, and 3 footprint.
The platform generates a single CRP document that meets PPN 06/21 requirements, including your organisational boundary statement, baseline emissions, current year emissions, and reduction targets. For multi-site organisations, the CRP includes a clear breakdown showing how individual locations contribute to the overall footprint, giving procurement teams the transparency they expect when evaluating bids for government and NHS contracts.
Awais built CarbonPass to help UK SMBs navigate PPN 006 procurement requirements without expensive consultants. With a background in technology and compliance, he's focused on making carbon reporting accessible and affordable for small businesses bidding for government and NHS contracts.
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CarbonPass Business consolidates emissions across all your locations into one CRP.
View Business plan →No. PPN 06/21 requires one Carbon Reduction Plan per organisation, not per site. Your CRP must consolidate emissions from all locations under your operational control into a single document. You may include a per-site breakdown for transparency, but the submission is always one unified plan.
Apply the same methodology consistently across all office types. Use DEFRA 2024 emission factors for electricity, gas, and other fuels regardless of whether the site is a warehouse, retail unit, or traditional office. The key is to collect the same categories of data from each location and apply the same conversion factors throughout.
Large sites will naturally dominate your total footprint, and that is expected. Include a per-site breakdown in your CRP so procurement teams can see the distribution. Focus reduction targets on your highest-emitting sites first, as this will have the greatest impact on your overall organisational emissions.
Yes. Under PPN 06/21, all site types must be aggregated into one organisational footprint. You should report total Scope 1, 2, and 3 emissions across all locations. However, separating site types in your internal methodology helps identify where emissions are concentrated and where reductions are most achievable.
For sites that opened partway through your reporting year, report actual emissions for the period they were operational. Do not annualise or extrapolate the data. In your baseline year calculation, note which sites were operational for partial periods and adjust your year-on-year comparisons accordingly to ensure fair comparison.
Use DEFRA 2024 UK Government conversion factors for all UK sites. These factors cover electricity, natural gas, transport fuels, and other common emission sources. If you have sites outside the UK, the GHG Protocol recommends using country-specific grid emission factors for electricity and DEFRA factors for other sources where local equivalents are unavailable.
CarbonPass Business plan lets you enter energy and activity data for each site separately, then automatically consolidates everything into one organisational footprint. It applies the correct DEFRA emission factors, calculates per-site and aggregate totals, and generates a single CRP document ready for procurement submission.