Less fuss, more certainty: From WREN to WE

A small change in wording can make a big difference. Under Section 20 of the Nigeria Tax Act, 2025, the old four‑part test for allowable business expenses — Wholly, Reasonably, Exclusively, and Necessarily (WREN) — has been pared down to two clear criteria: Wholly and Exclusively (WE). That might sound like a minor edit, but for taxpayers, accountants and tax administrators, it quietly rewrites how disputes will be fought and settled.

For years, the toughest arguments between taxpayers and tax authorities centred on the meanings of “reasonable” and “necessary”. Those words invited judgement calls. Was an expense “reasonable” if the business owner thought so but the auditor disagreed? Was something “necessary” only if a tax inspector had made the same decision? Those grey areas fuelled prolonged audits, appeals and unpredictability.

“Tax disputes should fall, because the authority can no longer argue that an expense was not “reasonable” simply because they would not have chosen it.”

The new WE standard removes much of that subjectivity. If an expense is incurred wholly and exclusively in the course of your business, it qualifies as deductible — provided it is not capital in nature or specifically excluded by law. In practice, this means tax officials should stop second-guessing commercial decisions and instead ask a simpler question: Did this cost relate solely to the business activity?

The benefits are straightforward. Tax disputes should fall, because the authority can no longer argue that an expense was not “reasonable” simply because they would not have chosen it. Businesses gain greater certainty about their tax position. Tax administration becomes more predictable and, importantly, less adversarial. Audits that once turned on subjective assessments are now more likely to hinge on clear documentary proof.

That said, the WE test is not a free pass. Expenses still must be genuinely business‑related. Costs that are capital in nature — the purchase of buildings, land, or assets normally written off through capital allowances — remain outside the ordinary deduction rule unless the Act specifically allows it. Equally, the legislature has listed items that are expressly non‑deductible; those remain off the table.

Documentation now matters more than ever. Under the simplified WE test, the conversation during an audit is likely to move quickly from “Was it reasonable?” to “Can you prove it was wholly and exclusively for the business?” Receipts, contracts, invoices, bank statements and contemporaneous internal records will be the decisive evidence. Electronic records, clear memos of business purpose, and linked invoices that show a direct commercial connection will make the difference between acceptance and challenge.

This shift also affects tax planning and corporate governance. Business owners should formalise decision‑making and keep written records whenever they commit funds for services, promotions, travel, or other operating expenses. Board minutes, approval emails and vendor contracts that explain the business rationale will support the WE position. For professional practices and companies that mix personal and business use of assets, accurate allocation and transfer pricing documentation, where relevant, become essential.

Accountants and tax advisers must update their checklists. Where previously a professional might have debated whether an expense was “reasonable” in the light of industry practice or company policy, the focus will now be on establishing exclusivity and direct business purpose. Auditors will look to see whether expenses can be traced to revenue‑generating activities or ordinary operations of the business, not whether the expenditure matched an inspector’s subjective standard.

For small businesses, the practical takeaway is simple: tidy records and clear justifications protect you. Many SMEs rely on informal bookkeeping and verbal explanations; under the WE regime, that casual approach carries increasing risk. Digital accounting with attachments for every invoice, prompt reconciliation between bank statements and ledgers, and a habit of documenting why each expenditure was made will guard against needless headaches.

Ultimately, the move from WREN to WE recognises a core principle of taxation: tax law should measure profit, not second-guess every managerial choice. The new standard steers the conversation back to numbers and substance rather than taste and opinion. It lowers the temperature in many audit rooms and raises the bar for evidence.

The law’s simplification is a welcome step toward clarity, but it brings with it a new discipline. If you want deductions to stick, make them clearly business‑linked and back them up with solid records. In the end, the winners in this new phase will be the taxpayers and advisers who treat documentation not as paperwork, but as protection.

Dr Adeniyi Bamgboye, DBA, FCTI, FCA, FCCA, a dual-qualified chartered accountant, tax expert, and policy analyst, is the managing partner of Empyrean Professional Services, an audit, business, and financial advisory firm dedicated to enhancing its clients’ business value. 08060603156. [email protected]