If you are missing cost basis there is historical data to provide up to 10 years of daily historical stock prices and volumes for each stock. They may have the split dates/spin off data too. Here is a link for researching historical cost basis: Find old stock-cost-basis
- Go online for historical stock prices
- For example, view the historical section at Marketwatch or Nasdaq (links are in the article above). It's generally acceptable to take the lowest and highest price from a given day and average them to arrive at a cost. It's also acceptable to use the closing price on the day of purchase.
- These free services may not include events that affect basis, such as reinvested dividends, spin-offs, and stock splits.
Have an amazing day. Evelyn M (CPA 20+ years)
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