By Sang Lee — Founder and Editor of AssetCalculus
Quick answer: If you buy 100 shares at $45, pay a $5 buy fee, and expect a $5 sell fee, the break-even sale price is $45.10 per share. Selling at the original $45 purchase price would still leave a $10 loss.
Break-even price matters whenever commissions, regulatory charges, spreads, or other transaction costs make the true cost higher than shares multiplied by the quoted price.
The Break-Even Formula
For flat buy and sell fees:
Break-even sale price = (Shares × Purchase price + Buy fee + Sell fee) ÷ Shares
Using 100 shares at $45 with $10 of total fees:
($4,500 + $5 + $5) ÷ 100 = $45.10
Profit or Loss at Different Sale Prices
| Sale price | Net proceeds | Profit or loss | Return on total cost |
|---|---|---|---|
| $40.00 | $3,995 | −$510 | −11.32% |
| $45.00 | $4,495 | −$10 | −0.22% |
| $45.10 | $4,505 | $0 | 0.00% |
| $50.00 | $4,995 | $490 | 10.88% |
| $58.00 | $5,795 | $1,290 | 28.63% |
Why the Purchase Price Is Not Always Break-Even
The purchase price excludes costs added to the trade. A buy fee increases total cost, while a sell fee reduces net proceeds. The share price must rise enough to cover both.
Even commission-free trading can involve bid-ask spreads, price movement during execution, regulatory fees, or currency conversion. Those costs may not appear as a simple flat field.
Break-Even Price by Share Count
With the same $10 in total flat fees, the per-share hurdle becomes smaller as the number of shares increases.
| Shares bought at $45 | Total fees | Break-even price |
|---|---|---|
| 10 | $10 | $46.00 |
| 50 | $10 | $45.20 |
| 100 | $10 | $45.10 |
| 500 | $10 | $45.02 |
If You Bought at Several Prices
First calculate the weighted average purchase price using the Average Cost Basis Calculator. Then use that average as the purchase-price input. For tax reporting, confirm the actual lot-selection method with the broker; an overall average may not be the basis assigned to a partial sale.
Taxes Are Separate From Trade Break-Even
The calculator’s break-even price is before income taxes. A realized gain can create a tax liability, and a loss may be subject to capital-loss and wash-sale rules. Tax outcomes depend on holding period, account type, jurisdiction, and individual circumstances.
Common Mistakes
- Using the quoted purchase price but excluding commissions and fees.
- Entering total transaction cost as a per-share price.
- Ignoring the selling fee when calculating break-even.
- Using the wrong tax lot after several purchases.
- Including dividends in one comparison but not another.
- Confusing a paper gain with a realized gain.
A Better Decision Checklist
- Confirm share quantity and cost basis.
- Add all acquisition costs that apply.
- Estimate sale fees and spreads.
- Calculate the pre-tax break-even price.
- Review tax lots and holding period.
- Compare the potential gain with the risk of continuing to hold.
Use the Calculator
Enter the trade into the Stock Profit/Loss Calculator. It shows total cost, net proceeds, dollar gain or loss, and percentage return. Use the CAGR Calculator if you also need an annualized return across several years.
Frequently Asked Questions
Does break-even include taxes?
No. It covers the entered transaction costs only.
What if there is no commission?
With zero entered fees, the mathematical break-even price equals the purchase price, although spreads or other costs may still exist.
Does receiving dividends lower break-even?
Dividends change total economic return, but this price-only calculator does not subtract them from cost basis or tax basis.
Bottom Line
For 100 shares purchased at $45 with $5 buy and sell fees, the pre-tax break-even price is $45.10. Small costs matter most on small trades. Use the correct share count, basis, and sale costs before deciding what price represents a true gain.
Official Resources
Educational purposes only. This calculation does not determine tax basis, tax liability, or whether a security should be sold.