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Strategic Management and Corporate Finance · Project Evaluation

How to Estimate Project Cash Flows in Capital Budgeting

Updated 11 October 2026 · Fact-checked

Estimating project cash flows means finding the extra after-tax cash a project brings to the firm in each year. You split it into initial outlay, yearly operating cash flow and terminal cash flow. Count depreciation only through its tax shield, include working capital changes, and ignore sunk and financing costs.

Understand Estimating Project Cash Flows

Capital budgeting decisions run on cash, not profit. Accounting profit includes non-cash items such as depreciation and ignores the money tied up in stock and debtors. So before you apply NPV, IRR or payback, you must first build a clean series of cash flows.

Every project has three phases. The initial outlay is the cash spent at time zero: purchase price, freight, installation, and extra working capital, less any cash from selling an old asset. The operating cash flows arise each year of the project's life. The terminal cash flow arises in the last year: salvage value (after tax) and recovery of working capital.

The guiding rule is the incremental cash flow principle. Count only cash flows that change because you accept the project: with-project minus without-project. This means you include opportunity costs (for example, rent you could earn on a spare building the project will use) and side effects on other products. You exclude sunk costs (money already spent, such as a feasibility study paid last year) and financing costs such as interest and dividends, because the discount rate already covers the cost of funds.

Depreciation is not a cash outflow. It matters only because it reduces taxable profit, which saves tax. That saving is the depreciation tax shield = depreciation × tax rate. This is why you add depreciation back after computing tax, or use the shortcut formula given below.

Working capital is an investment. You put it in at the start (or as sales grow) and, unless the question says otherwise, you get it back at the end of the project. It is a cash outflow and inflow, but it is never depreciated.

Key rules to remember

Initial outlay (new project)
Initial outlay = Cost of asset + Freight and installation + Increase in net working capital
Capitalised costs are part of the depreciable base. Working capital is not depreciated.
Initial outlay (replacement)
Net outlay = Cost of new asset + Increase in working capital − Sale proceeds of old asset ± Tax effect on sale of old asset
A taxable gain adds to the outlay as tax paid. A loss that can be set off reduces the outlay as tax saved. State your assumption.
Annual depreciation (SLM)
Depreciation = (Cost + Installation − Salvage value) ÷ Life in years
Use the method the question gives. For WDV, depreciation = opening book value × rate.
Operating cash flow (NOPAT method)
OCF = (Sales − Cash operating costs − Depreciation) × (1 − t) + Depreciation
Here t is the tax rate. Interest is excluded.
Operating cash flow (tax shield method)
OCF = (Sales − Cash operating costs) × (1 − t) + Depreciation × t
Gives the same answer as the NOPAT method. Use it as a check.
Terminal cash flow
Terminal CF = Salvage value − Tax on gain (or + tax saved on loss) + Recovery of working capital
Gain or loss is measured against the book value at the end of the project.
Tax on sale of asset
Tax effect = (Sale price − Book value) × t
Positive means tax payable. Negative means tax saved, if the loss can be set off against other income.
Incremental cash flow
Incremental CF = Cash flow with project − Cash flow without project
Use this for replacement and expansion decisions.

How to solve Estimating Project Cash Flows questions

Use the same order for any question. It keeps you from missing items and lets the examiner award step marks.

  1. 1Read the question and list what is given: costs, life, salvage, depreciation method, tax rate, working capital, and any old asset. Note anything to ignore, such as sunk costs and interest.
  2. 2Compute the initial outlay at Year 0: asset cost plus installation plus working capital, adjusted for any old asset sale and its tax effect.
  3. 3Compute annual depreciation on the depreciable base (cost plus installation, less salvage for SLM).
  4. 4Prepare a small table for each year: sales or savings, less cash costs, less depreciation, equals profit before tax, less tax, equals profit after tax, plus depreciation, equals operating cash flow.
  5. 5Compute terminal cash flow: after-tax salvage plus working capital recovery. Add it to the last year's operating cash flow.
  6. 6Show the final series of cash flows, Year 0 to the last year, with outflows as negatives.
  7. 7Apply the technique asked for (NPV, payback, IRR) only after the cash flows are settled, and state your assumptions in one line.

Quickest way: Tax shield shortcut

When to use it: Use it when operating cash flows are the same every year and you do not need a full profit statement.

  1. Compute annual depreciation once.
  2. Compute (Sales − Cash costs) × (1 − t).
  3. Add depreciation × t.
  4. The total is the yearly OCF. Repeat it for each year.
  5. Add salvage (after tax) and working capital recovery only to the final year.
  6. Check once by the NOPAT method for the first year.

Common mistakes in Estimating Project Cash Flows

  • Subtracting depreciation as a cash outflow, or forgetting to add it back

    Students treat the profit statement figure as cash.

    Fix: Deduct depreciation only to find tax. Then add it back, or use OCF = (S − C) × (1 − t) + Dep × t.

  • Including interest in operating cash flows

    Interest appears in the problem, so it feels like it must be used.

    Fix: Exclude financing costs. The discount rate covers them. Including interest double counts the cost of funds.

  • Including sunk costs, such as past market research

    The cost is real and sounds relevant to the project.

    Fix: Ask whether the cash changes if you accept the project. If not, ignore it. Include opportunity costs, even when no cash is paid.

  • Forgetting to recover working capital in the last year

    Working capital is treated as a one-time cost.

    Fix: Unless told otherwise, add the full working capital back as a terminal inflow. It is not taxed and no depreciation applies.

  • Ignoring the tax effect on sale of the old or terminal asset

    Students stop at sale price and skip the book value comparison.

    Fix: Always compare sale price with book value. Apply the tax rate to the gain or loss and state your assumption about set-off.

  • Depreciating installation costs wrongly, or leaving them out of the base

    Freight and installation look like expenses, not part of the asset.

    Fix: Capitalise freight and installation. Include them in the outlay and in the depreciable base.

Worked examples

Example 1

Surya Industries plans a new plant. Plant cost is ₹40,00,000, freight and installation ₹2,00,000, and extra working capital ₹3,00,000. Life is 5 years with salvage value ₹2,00,000 at the end, and depreciation is on the straight-line basis over the depreciable base. Expected annual sales are ₹30,00,000 and cash operating costs ₹16,00,000. Tax rate is 25%. Working capital is recovered at the end. Compute the cash flows for each year.

Show the solution
  1. Initial outlay = 40,00,000 + 2,00,000 + 3,00,000 = ₹45,00,000.
  2. Depreciable base = 42,00,000. Annual depreciation = (42,00,000 − 2,00,000) ÷ 5 = ₹8,00,000.
  3. Profit before tax = 30,00,000 − 16,00,000 − 8,00,000 = ₹6,00,000.
  4. Tax at 25% = ₹1,50,000. Profit after tax = ₹4,50,000.
  5. Operating cash flow = 4,50,000 + 8,00,000 = ₹12,50,000.
  6. Check by the shortcut: (30,00,000 − 16,00,000) × 0.75 = 10,50,000. Add 8,00,000 × 0.25 = 2,00,000. Total = ₹12,50,000.
  7. Book value at the end of Year 5 = 42,00,000 − 40,00,000 = ₹2,00,000. Salvage equals book value, so no gain or loss and no tax.
  8. Terminal cash flow = 2,00,000 + 3,00,000 = ₹5,00,000. Year 5 total = 12,50,000 + 5,00,000 = ₹17,50,000.

Answer: Year 0: −₹45,00,000. Years 1 to 4: ₹12,50,000 each. Year 5: ₹17,50,000.

Example 2

Kaveri Textiles considers replacing an old machine. The old machine has a book value of ₹6,00,000 and remaining life of 4 years with no salvage value, depreciated by straight-line at ₹1,50,000 a year. It can be sold now for ₹4,00,000. The new machine costs ₹14,00,000, has a 4-year life, no salvage value and straight-line depreciation. It will save cash operating costs of ₹3,00,000 a year. Tax rate is 25%. Assume the loss on sale of the old machine can be set off against other income of the firm, giving tax saving at 25%. Find the incremental cash flows.

Show the solution
  1. Loss on sale of old machine = 6,00,000 − 4,00,000 = ₹2,00,000. Tax saved = 2,00,000 × 25% = ₹50,000.
  2. Net initial outlay = 14,00,000 − 4,00,000 − 50,000 = ₹9,50,000.
  3. Depreciation on new machine = 14,00,000 ÷ 4 = ₹3,50,000. Incremental depreciation = 3,50,000 − 1,50,000 = ₹2,00,000.
  4. Incremental profit before tax = 3,00,000 − 2,00,000 = ₹1,00,000. Tax = ₹25,000. Profit after tax = ₹75,000.
  5. Incremental operating cash flow = 75,000 + 2,00,000 = ₹2,75,000.
  6. Check: 3,00,000 × 0.75 = 2,25,000. Add 2,00,000 × 0.25 = 50,000. Total = ₹2,75,000.
  7. Terminal cash flow is nil, as there is no salvage value and no working capital change.

Answer: Year 0: −₹9,50,000. Years 1 to 4: ₹2,75,000 each.

Exam tips

  • Show the Year 0 calculation as a separate working note. Examiners give marks for each component of the outlay.
  • Write your assumptions in one line, such as tax set-off on loss, working capital recovered at the end, and depreciation method used. This earns marks when the question is silent.
  • If the question gives interest or financing details, mention that you excluded them and why.
  • Always cross-check the first year's OCF with the tax shield formula before moving on to NPV.
  • In replacement questions, work with incremental figures. Do not compute separate cash flows for both machines unless asked.

Practice questions from Project Evaluation

Estimating Project Cash Flows in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Estimating Project Cash Flows: frequently asked questions

Why is depreciation added back when computing project cash flows?

Depreciation is a non-cash expense, so it must not reduce cash flow. You deduct it only to calculate tax, then add it back. Its real benefit is the tax saving of depreciation × tax rate.

Is working capital part of the initial outlay?

Yes. Extra working capital needed by the project is a cash outflow at the start. Unless the question says otherwise, you recover it in full as a terminal inflow in the last year.

Should interest be included in project cash flows?

No. Cash flows are calculated before financing costs. The cost of funds is captured in the discount rate, so including interest would count it twice.

What is an incremental cash flow?

It is the change in the firm's total cash flow caused by accepting the project. You include opportunity costs and side effects on other products, and you exclude sunk costs.