DRIP Calculator

What a DRIP is actually doing

A dividend reinvestment plan, or DRIP, uses each cash dividend payment to buy more shares of the same security instead of distributing the cash to the investor. Once that happens, future dividends are paid on a slightly larger share count, which is why reinvestment can create a snowball effect over long holding periods.

That snowball only works when the underlying company or fund continues paying dividends and when the reinvestment cost does not consume too much of the cash flow. A DRIP projection is therefore best understood as a planning model for long-horizon income growth, not as a promise that any one stock will continue paying or increasing dividends indefinitely.

The core maths behind dividend reinvestment

The model starts with an initial investment divided by the starting share price to find the opening share count. Each dividend period then pays cash equal to shares held multiplied by the dividend per share for that period. That cash is immediately used to buy additional shares at the prevailing share price.

Because both the share price and the dividend can change over time, the projection keeps updating those assumptions period by period. The ending value reflects the final share count multiplied by the ending share price, while forward annual income reflects the final share count multiplied by the final annualized dividend per share.

Worked example: 10,000 invested with quarterly reinvestment

Suppose 10,000 is invested at a starting share price of 45 with a 3.5% dividend yield, 5% annual dividend growth, 4% annual share-price growth, and quarterly reinvestment over 15 years. The projection shows not only the ending value, but also how many additional shares the reinvested dividends bought and how much forward annual dividend income the larger share count may be generating by the end.

That split matters. Two DRIP scenarios can produce similar ending values while having very different income profiles if one assumption set relies more heavily on dividend growth and the other relies more heavily on price appreciation.

DRIP versus taking dividends in cash

A useful dividend reinvestment calculator should not only show the DRIP ending value. It should also compare that result with a path where the investor takes after-tax dividends in cash while leaving the original shares invested. That comparison helps separate share-count compounding from the income you might have kept available for spending or reinvesting elsewhere.

The calculator now reports both the DRIP portfolio value and a no-DRIP total value that includes cash dividends taken. If the DRIP path finishes ahead, the difference shows the modeled benefit of buying more shares with dividends. If the cash-dividend path finishes ahead, the assumptions may be telling you that tax drag, partial reinvestment, weak price growth, or a falling share price reduced the advantage of automatic reinvestment.

Extra contributions, taxes, and partial reinvestment

Many investors combine a DRIP with regular new contributions. The annual extra contribution field spreads new money across the selected dividend periods so you can compare a pure reinvestment plan with a more realistic accumulation plan.

The dividend tax drag field is a planning input for taxable accounts. It reduces the dividend available for reinvestment before new shares are purchased. Tax-advantaged accounts may use zero for this field, while taxable accounts may need a rate that reflects qualified dividends, ordinary dividends, withholding, or the investor's local tax treatment.

The reinvestment percentage field handles partial DRIP behavior. A value of 100% models full reinvestment, 0% models taking dividends in cash, and values in between model taking some income while reinvesting the rest.

How to use the year-by-year projection

The projection table is meant to make the compounding path auditable. Each row shows the modeled portfolio value, ending shares, gross dividends, reinvested dividends, and forward annual income for that year. This helps you see whether the result is being driven mostly by price growth, dividend growth, recurring contributions, or additional shares bought through reinvestment.

Treat the table as a scenario, not a forecast. Real securities have irregular prices, dividend announcements, ex-dividend dates, payment timing, dividend cuts, dividend increases, plan fees, and tax details that can differ from a constant-growth model.

What this DRIP projection does not cover

Real DRIP plans can involve partial-share rules, delays between record date and reinvestment date, plan fees, withholding, dividend cuts, and price volatility that a simple projection cannot reproduce. Some plans also allow optional cash purchases, while others have narrower rules around purchases and sales.

Use the result as a disciplined planning estimate only. If you are evaluating a real company DRIP or brokerage reinvestment feature, compare this simplified projection with the plan documents, trading costs, and the company’s actual dividend policy.