How to calculate WACC in NEPSE: your real cost with bonus and right shares
You bought the same stock three times at three prices, then a bonus came, then a right issue - and now you want to know one thing: at what price do you actually make money? The number that answers it is your weighted average cost, or WACC, and it is the figure Mero Share and your broker use for your profit and your tax. This guide shows how to calculate WACC in NEPSE step by step, what bonus and right shares do to it, and how to turn it into your real profit after costs and capital gains tax.
What WACC means
WACC is the average price you paid per share, counting every purchase, every buying charge and every free share you received:
WACC = total money spent on the shares ÷ total shares you hold
Three things make it different from the simple average of your buying prices:
- Weighting. A purchase of 1,000 shares counts ten times as much as a purchase of 100 shares.
- Buying charges. Broker commission, the SEBON fee and the DP charge on each purchase are part of what you paid.
- Bonus and right shares. They add shares (and, for rights, money) to the pool, so they change the average.
Selling does not change WACC. When you sell part of a holding, the shares leave at the average cost, so the shares you still hold keep the same WACC.
Step 1: add up each purchase with its charges
On every buy you pay the price times the quantity, plus commission (a percentage of the trade amount that falls as the trade gets bigger), the SEBON fee and a small DP charge. The current rates are on our free NEPSE share calculator, which uses exactly the same schedule as the portfolio tracker.
Our worked example uses invented prices, with the rates in force in November 2026:
| Purchase | Amount | Commission | SEBON fee | DP charge | Total paid |
|---|---|---|---|---|---|
| 100 shares at Rs 400 | Rs 40,000 | Rs 144.00 | Rs 6.00 | Rs 25 | Rs 40,175.00 |
| 50 shares at Rs 300 | Rs 15,000 | Rs 54.00 | Rs 2.25 | Rs 25 | Rs 15,081.25 |
| 150 shares | Rs 55,256.25 |
WACC after the two purchases = 55,256.25 ÷ 150 = Rs 368.38. The simple average of the two prices would give Rs 350, and the plain weighted price without charges Rs 366.67 - so charges and weighting both matter, even before any bonus.
Step 2: add a bonus issue
A bonus issue gives you extra shares for nothing. It does not add value to the company, so the market price adjusts down (see our guide to bonus, right shares and cash dividends). Your cost per share falls in the same way.
In Mero Share's purchase source, each bonus share is counted at its face value of Rs 100. Suppose a 20% bonus arrives on our 150 shares:
- New shares: 150 × 20% = 30, counted at Rs 100 = Rs 3,000.
- Total cost: 55,256.25 + 3,000 = Rs 58,256.25 for 180 shares.
- New WACC: 58,256.25 ÷ 180 = Rs 323.65.
Your stock did not get cheaper by magic: you hold more pieces of the same company, and the cost is spread over all of them. Check your own figure under My Purchase Source in Mero Share, because it is the number your sale will be measured against. If it differs from your own working - for example because shares moved in from another account - trust Mero Share's figure and type it into the portfolio tracker.
Step 3: add a right issue
Right shares cost money - usually Rs 100 each. If you subscribe, treat them as one more purchase at the price you paid. Say a 25% right is offered on the 180 shares: you take up 45 shares and pay 45 × 100 = Rs 4,500.
- Total cost: 58,256.25 + 4,500 = Rs 62,756.25 for 225 shares.
- New WACC: 62,756.25 ÷ 225 = Rs 278.92.
If you do not subscribe, your WACC stays at Rs 323.65 and your holding is diluted. Our free right share calculator shows what a right issue does to your holding and what skipping it costs.
Step 4: from WACC to your real profit
Now sell 100 of the 225 shares at Rs 330:
| Line | Working | Rs |
|---|---|---|
| Sale amount | 100 × 330 | 33,000.00 |
| Selling costs | commission 118.80 + SEBON 4.95 + DP 25 | 148.75 |
| Cost of those shares | 100 × 278.92 (WACC) | 27,891.67 |
| Profit after costs | 33,000 - 148.75 - 27,891.67 | 4,959.58 |
| Capital gains tax, held 365 days or less | 10% of the profit | 495.96 |
| Capital gains tax, held longer | 7.5% of the profit | 371.97 |
| Profit in your pocket | 4,463.62 (or 4,587.61) |
The tax is charged on the profit after costs, and only on a profit - never on a loss. Individuals pay the lower rate if they held for more than 365 days; the rates are set in the budget each year, so check the current ones before you sell. For why a small price rise can still leave you at zero, see the real cost of a NEPSE trade.
A useful by-product is your break-even price: the sale price at which the proceeds after selling costs exactly equal the cost. In this example it is about Rs 280.23 - just 0.5% above the WACC.
Compare that with measuring the sale against your original average buying price of Rs 366.67: you would have believed that Rs 330 was a loss of over Rs 3,600 on these 100 shares, when it was in fact a profit of nearly Rs 5,000. Using the wrong average can make a winning sale look like a losing one.
Common mistakes
- Comparing today's price with an old unadjusted buying price. After a bonus or right issue the price adjusts, so your cost must be adjusted too. Compare the market price with your WACC, not with the price you first paid.
- Forgetting the charges. They are small on one trade but add up over many buys.
- Averaging down without recounting. Each extra purchase moves WACC toward the new price, but never all the way.
- Ignoring the date. Shares are sold oldest-first, and the 365-day line decides your tax rate.
Let the tools do the arithmetic
You can do all of this by hand, but the portfolio tracker works out your WACC through every purchase, bonus and sale, applies the right tax rate by date, and shows your gain after costs - and its tax report totals the year for you. Enter your Mero Share WACC if you want it to follow your official figure. Start your free 7-day trial to keep your whole portfolio in one place, or sign in if you already have an account.
Quick answers
Does a bonus issue lower my WACC? Yes - your cost is spread over more shares, and the market price adjusts down by the same logic.
Does selling change WACC? No. The shares you keep stay at the same average cost.
Are bonus shares free for tax purposes? They are counted in WACC at Rs 100 each, as Mero Share records them; tax on the bonus itself is a separate matter.
Where do I see my official WACC? In Mero Share, under My Purchase Source.
This guide explains a method with invented numbers, not investment or tax advice. Rates are as published in November 2026; check with your broker and a tax adviser.
Source: MacroLens NP analysis of NEPSE data. Cover photo: public domain.
