Deferred taxes and book vs cash
Why companies report different tax numbers to shareholders and the government — and how it flows through the statements.
The core problem
When a company files its tax return, it follows tax rules set by the government. When it publishes its financial statements, it follows book rules (GAAP or IFRS). These two sets of rules often disagree on when revenue is recognised or when an expense is deductible.
The result: the tax expense on the Income Statement (book taxes) rarely matches the actual cash taxes paid to the government. The gap between the two creates deferred tax assets and deferred tax liabilities on the Balance Sheet.
Understanding this is essential for IB interviews because it shows up in:
- Walk-me-through-the-statements scenarios
- DCF analysis (deferred taxes affect true cash flow)
- M&A (purchase price allocation creates new deferred tax items)
- LBO modelling (tax shields from leverage)
Book taxes vs cash taxes
| Book taxes (Income Statement) | Cash taxes (paid to government) | |
|---|---|---|
| What it follows | GAAP / IFRS | Tax code (HMRC / IRS) |
| Where it shows up | "Income Tax Provision" on the IS | Actual payment, visible in CFS or tax return |
| Purpose | Match tax expense to the period's revenue | Minimise current cash tax bill legally |
The Income Tax Provision on the IS can be split into two components:
- Current Tax Expense ≈ what you actually pay in cash this period
- Deferred Tax Expense ≈ the portion you'll pay (or save) in the future
Deferred Tax Liabilities (DTL)
A DTL arises when you pay less tax now than your book tax expense. You're deferring the payment to the future.
The most common cause: accelerated depreciation.
For book purposes, a company might depreciate a $100 machine over 10 years (straight-line, $10/year). For tax purposes, the government lets the company depreciate it faster — say $25 in Year 1.
| Book | Tax return | |
|---|---|---|
| Depreciation Year 1 | $10 | $25 |
| Taxable income (lower = less tax) | Higher | Lower |
| Tax paid | Higher on paper | Lower in cash |
The company reports a higher tax expense on its Income Statement than it actually pays. The difference sits on the Balance Sheet as a Deferred Tax Liability — tax you owe the government in the future.
On the statements:
- IS: Tax expense reflects the full book rate
- CFS: DTL increase is added back (source of cash) because you paid less cash than the IS shows
- BS: DTL ↑ (long-term liability)
You're effectively borrowing from the government by paying less tax now. You'll repay it in later years when tax depreciation runs out but book depreciation continues.
Deferred Tax Assets (DTA)
A DTA arises when you pay more tax now than your book tax expense. The government owes you a tax benefit in the future.
Common causes:
- Net Operating Losses (NOLs): The company lost money in prior years. Tax rules let you carry those losses forward to offset future taxable income, reducing future cash taxes.
- Bad debt reserves: The company writes off receivables for book purposes before the tax code allows the deduction.
- Accrued expenses: Certain liabilities (like warranty reserves) are deductible for book purposes before they're deductible for tax purposes.
On the statements:
- IS: Tax expense may be higher than what the company actually owes long-term
- CFS: DTA increase is subtracted (use of cash) because the company paid more in cash than the IS implies
- BS: DTA ↑ (long-term asset — it represents future tax savings)
If a company doesn't expect to generate enough future taxable income to use its DTAs, it must record a valuation allowance — essentially writing down the DTA. This is common for loss-making companies and can be a big red flag in analysis.
How deferred taxes flow through all three statements
Let's say a company has $15 more in book depreciation than tax depreciation (unusual — normally it's the reverse for DTLs, but this illustrates a DTA).
Scenario: DTA increases by $6 (= $15 × 40% tax rate)
- Income Statement: No change to Pre-Tax Income. Tax expense on the IS is lower than what the company actually paid in cash.
- Cash Flow Statement: Net Income is higher (lower IS tax expense), but you subtract the DTA increase in the working capital / non-cash section because the cash tax bill was actually higher.
- Balance Sheet: DTA ↑ by $6 (asset). Cash ↓ by the extra tax paid. Retained Earnings ↑ by the higher Net Income. Balance Sheet still balances because the DTA makes up the gap.
The reverse logic applies to a DTL increase — Net Income is lower (higher IS tax expense), but you add back the DTL increase on the CFS because cash taxes were lower.
The interview questions you'll get
"What's the difference between a deferred tax asset and a deferred tax liability?"
A DTA means the company has paid more tax in cash than what shows on its Income Statement — it has a future tax benefit. A DTL means the company has paid less tax in cash than what shows on its Income Statement — it has a future tax obligation. The most common cause of DTLs is accelerated depreciation for tax purposes, and the most common cause of DTAs is net operating loss carryforwards.
"How do deferred taxes affect the cash flow statement?"
An increase in the Deferred Tax Liability is added back on the CFS (source of cash) because the company's actual cash tax payment was lower than the Income Statement tax expense. An increase in the Deferred Tax Asset is subtracted on the CFS (use of cash) because the company paid more in cash taxes than shown on the IS.
"A company has a net operating loss of $100. How does this affect the statements going forward?"
The NOL creates a Deferred Tax Asset of $100 × the tax rate. In future profitable years, the company uses the NOL to reduce its taxable income, so it pays less cash in taxes. The DTA decreases as the NOL is used up, and the company's cash flow benefits from the tax savings.
"Deferred taxes exist because book rules and tax rules disagree on timing. A DTL means you owe the government later; a DTA means the government owes you later. The most common example is accelerated depreciation creating a DTL."
Why this matters beyond accounting interviews
Deferred taxes come back in every advanced topic:
- DCF: When projecting free cash flow, you need to estimate cash taxes, not book taxes. If a company has large NOLs, its cash tax rate could be near zero for years.
- M&A: Purchase price allocation often creates new intangible assets that are amortised for book but not tax purposes (or vice versa), creating new deferred tax items.
- LBO: The interest tax shield from leverage reduces cash taxes, and sponsors actively plan around the tax impact of debt structures.
Get comfortable with the concept here and it'll pay dividends (pun intended) in every later topic.