Easy way to calculate capital gains tax on DRIP shares

Anyone who has reinvested dividends for years eventually faces the bookkeeping headache this reader describes: shares of a bank bought decades ago, topped up again and again through a dividend reinvestment plan and optional purchases, now grown into a sizeable holding with a murky cost base. This piece tackles the practical problem of figuring out the taxable gain when every reinvested dividend counted as a fresh purchase at that day's price. The thinking it works through is how to reconstruct the adjusted cost base properly, why each reinvestment adds to what you paid rather than being free, and how to keep the math manageable so the eventual sale is reported correctly. It's a useful, down-to-earth read for long-time DRIP investors and dividend-focused savers who have let the records pile up and want a clear way to sort out what they actually owe when they sell.