Covered Call Calculator

About the Covered Call Calculator

A covered call is one of the most popular options strategies for people who own shares. You sell someone else the right, but not the obligation, to buy your shares at a set price, the strike, before a set date, the expiry. In return you receive a payment called the premium, which is yours to keep whatever happens. The call is "covered" because you own the shares you might have to deliver. The strategy turns shares into a source of income, at the cost of giving up gains above the strike.

This covered call calculator shows what a covered call can earn. Enter your cost per share, the number of shares, the strike, the premium and the days to expiry. It works out the premium income, the return if the shares are not called away and if they are, both annualised, the breakeven price and the maximum profit.

How to Use the Covered Call Calculator

Enter the stock price or your cost per share and the number of shares.

Enter the call's strike price, the premium per share and the days to expiry.

The Formulas

  premium income    = premium × shares
  static return     = premium ÷ cost
  if-called return  = (strike − cost + premium) ÷ cost
  annualised        = return × 365 ÷ days
  breakeven         = cost − premium
  maximum profit    = (strike − cost + premium) × shares

Step-by-Step Example

100 shares bought at 50, a 30-day call with a 55 strike sold for 1.50.

  premium      1.50 × 100 = 150
  not called   1.50 ÷ 50 = 3%, about 36.5% a year
  called       (55 − 50 + 1.50) ÷ 50 = 13%
  breakeven    50 − 1.50 = 48.50
  max profit   6.50 × 100 = 650

The Three Outcomes

At expiry, one of three things has happened. If the stock is below the strike, the call expires worthless; you keep the shares and the premium, earning the static return, and can sell another call. If the stock is above the strike, the buyer exercises and your shares are sold at the strike; you keep the premium plus any gain up to the strike, the if-called return. If the stock has fallen sharply, you still keep the premium, but your shares are worth less; the premium only offsets part of the loss.

Choosing a Strike

The strike sets the trade-off between income and upside. An at-the-money strike, near the current price, pays the highest premium but is likely to be exercised. An out-of-the-money strike, above the price, pays less but leaves room for the shares to rise before being called away. Many investors choose a strike they would be happy to sell at, so being called away is a good outcome rather than a regret.

Choosing an Expiry

Short-dated options, from a week to a month or two, lose value quickly as expiry approaches, which works in the seller's favour. Selling monthly calls repeatedly can generate a steady income stream. Longer-dated calls pay more premium in total but less per day, and tie up the shares for longer. The annualised return helps compare different expiries on equal terms, although repeating the same return every month is not guaranteed.

Risks and Costs

A covered call does not protect against a large fall in the share price. Upside is capped, so in a strong rally you miss out on gains above the strike. Shares may be called away early, especially just before a dividend. Commissions, the bid-ask spread and taxes reduce the returns shown here. In many countries, options trading requires approval from your broker, and covered calls in tax-advantaged accounts follow special rules.

Dividends

If the shares pay a dividend before expiry and you still own them, you receive it, which adds to the static return. The calculator leaves dividends out, so add them separately if relevant.

Rolling a Covered Call

If the stock rises towards the strike before expiry and you would rather keep the shares, you can buy back the call and sell a new one with a higher strike or later expiry, known as rolling up or out. Rolling often costs money when the stock has risen, so compare the cost of buying back the call with the extra premium from the new one.

Covered Calls Versus Dividends

Both produce income from shares, but they behave differently. Dividends are paid by the company and do not limit your upside. Call premiums are paid by the option buyer in exchange for some of your upside. Many income investors combine the two, writing calls on dividend-paying shares, but should remember that the total return in a strong market will lag simply holding the shares.

Tax Considerations

In many tax systems, option premiums are treated as short-term gains when the call expires or is bought back, and as part of the sale price if the shares are called away. Some covered calls can affect the holding period of the shares for long-term capital gains purposes. Check how your country taxes options.

Understanding Your Result

The headline gives the premium income.

The returns line gives the static and if-called returns, annualised.

The breakeven line gives the price at which you start to lose money.

The maximum profit line gives the most the position can make.

When Should You Use This Calculator?

Use it to compare strikes and expiries before selling a call.

Use it to check whether a premium is worth giving up the upside.

Use it to estimate income from a covered call strategy.

Common Mistakes

Treating premium as protection. It only offsets a small fall.

Ignoring the cap. Gains above the strike go to the buyer.

Annualising unrealistically. Monthly premiums vary.

Forgetting costs and taxes. They reduce real returns.