Mandatory Payrolling 2027: The EV Data Handoff to Fix Now

From 6 April 2027, employers will have to report company cars, car fuel, vans, van fuel and employer-provided medical benefits through payroll software and Real Time Information. For many EV fleets, the hard part will not be calculating one more number. It will be getting accurate vehicle and employee changes from Fleet to Payroll before the relevant payroll submission.

HMRC is already telling employers to prepare their software, map the benefits they provide and decide how they will handle joiners, leavers and benefits that change in value. Its latest update says final guidance and legislation for the first phase are expected in autumn 2026.

That makes September a useful time to test the operating process, while there is still time to fix ownership, timing and evidence gaps.

This article reflects HMRC material available on 2 September 2026. Some operational details remain subject to final legislation and guidance. It is general operational information, not tax or legal advice.

What is changing in April 2027

Today, most benefits in kind are reported annually on form P11D for Income Tax, although voluntary real-time payrolling already exists. HMRC's July 2026 policy paper confirms a phased move to mandatory real-time reporting.

The first phase, from 6 April 2027, covers:

• company cars

• car fuel

• vans and van fuel

• employer-provided medical benefits

  Most remaining in-scope benefits are due to follow from April 2028. Loans and accommodation have different transitional treatment.

  For the first phase, HMRC says employers should ensure their payroll software can support the required real-time reporting by April 2027. They should also plan for employees who join or leave during the year, benefits whose value changes and underpayments or overpayments.

  This is not only a Payroll-system project. Payroll cannot report a car change it has not received, cannot apply the correct effective date if Fleet sends a month-end summary late and cannot explain an amendment if there is no change record.

Keep car-benefit reporting and mileage reimbursement separate

There are two related but different processes.

The first is the reporting and taxation of the company car and any relevant car-fuel benefit. That is the process moving into mandatory real-time payrolling.

The second is reimbursement for qualifying business mileage in a fully electric company car. HMRC's Advisory Electric Rate can be used for that reimbursement, or an employer can use another evidenced rate that reflects its circumstances. That process needs the journey, vehicle, rate, charging basis and approval evidence behind the payment.

One process does not replace the other. A monthly mileage total is not a complete company-car benefit record. Equally, a company-car record does not prove that a mileage claim relates to qualifying business travel or that the correct electric reimbursement method was used.

The practical goal is therefore not one giant spreadsheet. It is two controlled records joined by stable employee and vehicle identifiers.

The minimum handoff from Fleet to Payroll

HMRC's current guidance for employers already payrolling car and car-fuel benefits lists data including the car's make and model, first-registration date, fuel type, car identifier, calculated price, availability dates and relevant taxable amount. It recommends using a car identifier that distinguishes the vehicle allocated to an employee, such as the registration number.

The final 2027 specification may refine the operational requirements. Even so, Fleet and Payroll can test these core controls now.

1. One employee and one vehicle identifier

The same employee and vehicle references should appear in the fleet register, benefit record and company-EV mileage process. Free-text entries such as “Tesla” or “electric car” are not enough to distinguish two vehicles or detect a replacement.

2. Effective dates, not just month labels

Record when the car became available, when it stopped being available and when any relevant vehicle or benefit detail changed. Payroll needs the actual effective date, not simply “September fleet update”.

3. A named owner for every change

Define who records a new car, replacement, leaver, fuel provision change or correction. Set a cut-off for the payroll period and an escalation route for changes received after that cut-off.

4. A visible amendment trail

HMRC's current car-data guidance contains specific correction and amendment processes. Internally, every changed field should retain the previous value, new value, effective date, source and approver. Do not overwrite the old record and leave Payroll to infer what happened.

5. A reconciliation between the two processes

At least monthly, compare the population of fully electric company cars in the fleet register with:

• the company-car population sent to Payroll

• employees submitting company-EV mileage claims

• vehicles and employees added, removed or changed during the period

  Differences may be legitimate, but they need an owner and an explanation.

The separate mileage reimbursement record

For each in-scope company-EV business-mileage payment, keep enough information to reproduce the decision:

• employee and company-car identifiers

• journey date, business purpose and approved business miles

• charging basis required by the employer's policy

• the rate and policy version in force on the journey date

• calculation and payment references

• evidence and approval for any exception

  Keep employee-owned cars, vans, hybrids, private travel and ordinary commuting outside this standard company-car reimbursement route. They do not become in scope merely because electricity was purchased.

  This separation also helps Payroll investigate a mismatch. If the employee appears in the mileage file but no company EV is assigned in the fleet register, the claim can be paused before the payment is coded. If a vehicle replacement appears in Fleet but not Payroll, the benefit record can be corrected without rewriting the mileage evidence.

A practical readiness test for September

Run one sample month through the future handoff and answer six questions.

1. Can Payroll match every company car to one employee and one stable vehicle identifier?

2. Can Fleet show the exact date for every car assignment, withdrawal and replacement?

3. Can the process identify changes that arrived after the payroll cut-off?

4. Can Payroll distinguish the company-car benefit record from an electric business-mileage reimbursement?

5. Can Finance reproduce the rate, evidence and approval used for each sampled EV mileage payment?

6. Can the three teams reconcile additions, removals, claims and corrections without relying on an email search?

   If any answer is no, write down the missing field, its source, the owner who supplies it and the deadline within the payroll cycle. That turns “prepare for 2027” into a concrete control change.

What is confirmed and what still needs watching

HMRC has confirmed the 6 April 2027 start date and the first group of benefits, including company cars and car fuel. It has also told employers to prepare payroll software and the processes for employee and benefit changes.

However, HMRC says final guidance and legislation for the first phase are expected in autumn 2026. Employers should therefore avoid hard-coding assumptions that have not been confirmed. Keep a named owner for monitoring the final rules and updating the payroll specification, employee communication and control documentation.

The sensible work now is the work that will still be needed under any final specification: reliable identifiers, effective dates, data ownership, change records, reconciliations and a separate evidence trail for company-EV mileage reimbursement.

Official sources available on 2 September 2026

• HMRC, Changes to reporting of benefits in kind from April 2027

• HMRC, The default operation of mandatory payrolling

• HMRC, Issue 146 of Agent Update

• HMRC, Sending car data to HMRC: payrolling car benefit and car fuel benefit

• HMRC, Advisory fuel rates

Fix the reimbursement layer before it reaches Payroll

The Company EV Reimbursement Pack turns one UK entity's current company-EV mileage method, sample claims and evidence into a documented policy, rate decision and set of Payroll controls.

The standard pilot price is £990 excluding VAT and delivery is within three UK business days after complete inputs. For the standard B2B supply from BEASIGHT in France to a UK business, no VAT is charged by the seller and the customer accounts for UK VAT under the reverse charge where required. It does not implement payroll software, calculate company-car benefits or provide tax or legal advice. Its role is narrower: make the mileage reimbursement layer clear, reviewable and ready to hand into the wider Payroll process.