The short answer
Documentation decides deductibility. An expense you cannot support is an expense you cannot subtract from income, which means tax computed on a larger profit than the business actually made. For construction businesses specifically, that plays out against how the trade already sells and to whom.
Expenses and deductibility for construction businesses
Materials bought per project and consumed on site, where site wastage and pilferage are significant and cost overruns are discovered only after they have happened. That is the background against which expenses and deductibility has to work in this trade.
What invoicing actually looks like here
Invoice trade tied to certified progress, retention and often withholding tax. Material purchases must carry compliant invoices too, because the deductibility of project costs depends on it.
What the rules say
This page explains how a requirement generally works. It is not tax advice, and it cannot account for the specifics of any one business. For a position you intend to rely on, confirm with KRA directly or with a registered tax agent.
Tax rules in Kenya change with each Finance Act and with regulations made during the year. Before acting on any figure, deadline or threshold, check the current position on KRA's own website.
What we are not stating here. Some of the specific requirements relating to this topic have not yet been verified against their primary source by our reviewer, so they are withheld from this page rather than stated from memory. That means you will not find a threshold, rate, deadline or penalty figure below. For those, check KRA directly. Everything else on this page explains how the mechanism works and is not affected.
Why this is the part that changes behaviour
Compliance requirements tend to be treated as an administrative cost until they touch the money. The link between the documentation supporting an expense and whether that expense can be claimed is where this stops being administration. An expense you cannot support is an expense you cannot deduct, which means tax computed on a larger profit than you made.
The buying side is where the exposure sits
Businesses focus on the invoices they issue. The greater exposure is usually in the invoices they receive, because that is where deductions come from. A business that buys from a supplier who cannot issue a compliant invoice is carrying the cost of that, quietly, all year, and discovers it at the point of computing its position.
What good practice looks like
Know which of your suppliers can issue a compliant invoice and which cannot, before the year ends rather than after. Keep what they issue somewhere you can retrieve it. The businesses that find this painless are not the ones with the best software; they are the ones who file as they go.
Where this goes wrong
- Material wastage and site pilferage
- Progress billing disputed by clients
- Retention held for months after completion
Common questions
Does a construction business need to issue a tax invoice for every sale?
Invoice trade tied to certified progress, retention and often withholding tax. Material purchases must carry compliant invoices too, because the deductibility of project costs depends on it.
What usually goes wrong with records in a construction business?
The recurring problems in this trade are material wastage and site pilferage; progress billing disputed by clients; retention held for months after completion; subcontractor payments against certified work. Each of them shows up in the records before it shows up in the bank balance.
How should a construction business keep stock records?
Materials bought per project and consumed on site, where site wastage and pilferage are significant and cost overruns are discovered only after they have happened. Records that do not reflect that pattern will not tell you anything useful, whatever system produces them.
How do I know this information is current?
Tax rules in Kenya change with each Finance Act and with regulations made during the year. Before acting on any figure, deadline or threshold, check the current position on KRA's own website.
Sources
- officialKenya Revenue Authority — Kenya Revenue Authority, checked 2026-09-18
- officialTax Procedures Act, 2015 (Act No. 29 of 2015) — National Council for Law Reporting (Kenya Law), checked 2026-09-18
- officialIncome Tax Act (Cap. 470) — National Council for Law Reporting (Kenya Law), checked 2026-09-18
- officialeTIMS (Electronic Tax Invoice Management System) — Kenya Revenue Authority, checked 2026-09-18
- officialFinance Act, 2023 (Act No. 4 of 2023) — National Council for Law Reporting (Kenya Law), checked 2026-09-18
- officialTax Procedures (Electronic Tax Invoice) Regulations, 2024 — Kenya Gazette / Kenya Law, checked 2026-09-18
- officialValue Added Tax Act, 2013 (Act No. 35 of 2013) — National Council for Law Reporting (Kenya Law), checked 2026-09-18
Further reading on Veira
- eTIMS compliance checklist for SMEsWhat to collect so expenditure stays claimable
Veira publishes this site. These are its own pages, offered because they cover the same ground, not as independent recommendations.