Form

NNDR1: national non-domestic rates - validation checks

Updated 17 December 2025

Applies to England

Please read this note before completing and submitting your NNDR1

1. The National Non-Domestic Rates Provisional Return (NNDR1) 2026-27 is designed to calculate and report your authority’s calculation of the estimated amount of non-domestic rates it will collect in 2026-27. On receipt of your form, we carry out a number of checks to satisfy ourselves that the form has been completed correctly. Where the data vary significantly from that provided on your NNDR1 for 2025-26, we seek an explanation for the variance. The main validation checks are contained in the sheets named ‘Main validation’ and ‘Supplementary validation’. The Department will always contact the named local authority contact to resolve an error or seek an explanation for any entries that fail our validation checks and no response has been provided.

2. It would be helpful if those that are completing the form can ensure that the information is checked against the following notes and, where necessary, provide an explanation for data that have failed our validation checks when the form is submitted to us. Please do not overwrite formula in order to resolve issues.

NNDR1 form

3. Please note that a number of checks and calculations are built into the NNDR1 form itself.  There are also a number of warnings that will appear if results appear to be incorrect. The form provides space on the validation sheet for authorities to comment on any data that fail the validation checks but are genuine, plus there is a general comments box at the bottom of the validation sheet.

4. Details of the checks that are incorporated in the NNDR1 form are set out below. Please note that, while we have tried to incorporate most of the checks into the validation sheet, we may need to contact local authorities for additional information following validation carried out after the data enters our database.

5. The Excel copy of the NNDR1 form should be returned to the department by 31 January 2026. It is important that this deadline is adhered to as we need to ensure the data are validated before they are published, when that data is passed on to the teams within MHCLG that calculates and arrange the schedules of payments between yourself and the department.

6. The Excel copy of the NNDR1 form should be sent by the Chief Financial or Section 151 officer with their e-signature and a confirmation they are happy with the figures in the form. This should also be submitted to the Department by 31 January 2026.This is required for the audit of our processes, and we will contact you if this has not been received.

7. If you become aware of an exceptional circumstance which prevents you from meeting this deadline, please contact us at nndr.statistics@communities.gov.uk.

General

8. A number of validations have also been included on the NNDR1 form in an attempt to prevent invalid or implausible values. If one of these occurs a message will appear either to ask for an explanation or asking that the entry is reviewed. Explanations should be sufficiently detailed to aid our understanding of the difference. Explanations such as “It’s OK/correct”, “Revaluation” or “None” will be followed up with a request to provide more detail.

9. Please follow any instructions to ensure the correct data entry. The forms have been protected to prevent incorrect data entry; please do not unprotect the worksheet as this will cause additional work for both us and you. Please contact us at nndr.statistics@communities.gov.uk if you believe that there is an error in your form.

10. Please ensure any data upload software you use adheres to the data entry rules (positive or negative as appropriate and always in whole £) in the correct cells; again failure to do so may cause additional validation work.

Arithmetic calculations and rounding

11. All data should be entered in whole pounds. Where possible calculations have been set to calculate to whole pounds.

12. Before returning the form, please ensure that all arithmetic calculations are correct. If you believe any of the calculations are not correct please contact us immediately; do not try and amend the form yourself.

Main validation tests

Test 1: Compares the total rateable value recorded in Part 2 Line 1 with VOA’s draft rating list data published on 26 November 2025.These are rounded to the nearest £1,000 but we expect that this will be the same.

Tests 2-8: Compares the total cost of various mandatory reliefs recorded in Part 2 with the equivalent total data from the 2025-26 NNDR1.

Tests 9-14: Compares the total cost of various discretionary reliefs recorded in Part 2 with the equivalent total data from the 2025-26 NNDR1.

Test 15: Compares the total net rates payable recorded in Part 2 Line 43 with the equivalent data from the 2025-26 NNDR1.

Test 16: Compares the total estimated repayments (appeals provision) recorded in Part 3 Line 3 with the equivalent data from the 2025-26 NNDR1.

Test 17: Checks that the value of the surplus / deficit on collection fund in respect of 2026-27 recorded in Part 4 Line 20 does not equal zero.An explanation is required if it does, as this would be unusual.

Test 18: Checks whether a positive figure has been entered in the sums written off line (Part 4 Line 3). Negative figures are expected in this line, so an explanation is required to explain why a positive figure is correct.

Test 19: Checks whether the collection fund opening balance in Part 4 Line 1a has been adjusted using Part 1 Line 1b. Note: The opening balance shown in Line 1a has been pre-populated with the closing balance in your NNDR3 2024-25, so it may be valid to adjust it via Line 1b if there has been a change to the collection fund balance following a completed audit. If so, please also make sure that a revised 2024-25 NNDR3 has also been submitted.

Test 20: Checks whether the other rates retention scheme charges entered on Part 4 Lines 13, 14, 15 and 16 have been overwritten. Note: These cells have been pre-populated with their corresponding values from the NNDR1 2025-26 form. We would not expect this to change and would need an explanation if this has done so.

Test 21: This shows the split of rateable value reported in each multiplier using data from in Part 1 Lines 1a to 1e. As this is the first year that this data has been collected, we would like to understand how the splits have been reached, and any reasons behind any significantly large or small percentage shares in one of the multiplier groups. This will aid our understanding of the data as it is received.

Supplementary validation

Test 1-6: Compares the number of hereditaments being granted various mandatory reliefs recorded in Supplementary Information lines 1c - 1h with the equivalent data from the 2025-26 NNDR1.

Tests 7-13: Compares the number of hereditaments being granted various discretionary reliefs recorded in Supplementary Information lines 1i - s with the equivalent data from the 2025-26 NNDR1.

Tests 14-17: Compares the number of hereditaments being granted or contributing to small business rates reliefs (SBRR) recorded in Supplementary Information lines 1a - 1b with the equivalent data from the 2025-26 NNDR1.

Test 18: Compares the number of hereditaments from the VOA data with the number of hereditaments recorded in Supplementary Information lines 2a and 2b column 1 (hereditaments as at 31 December 2025)

Test 19: Compares the number of hereditaments as at the 31 December 2025 snapshot (sum of lines 2a and 2b column 1) with the number of forecast hereditaments for 2026-27 (sum of lines 2a to 2e column 2)/

Tests 20-24:Compares the amounts of empty property relief being granted in different kinds of hereditaments recorded in Supplementary Information Part 3 with the equivalent data from the 2025-26 NNDR1.