Position Manager

Your broker shows what you hold, but a position manager adds value: tracking cost basis across multiple purchases, monitoring stops and targets, calculating metrics like portfolio weight, maintaining records for tax, and providing a consolidated view if you have multiple accounts.

Update after every trade (immediately or same day). Update prices at least weekly, daily if you actively monitor. Update for all corporate actions and dividends as they occur. Consistent updates prevent data from becoming stale and inaccurate.

For most Australian retail investors, Sharesight is excellent - it handles CGT, franking, and integrates with Australian brokers. For DIY, Google Sheets or Excel works well. For active traders with IBKR, their Trader Workstation provides comprehensive position management.

Add brokerage to total cost and calculate cost per share. If you buy 100 shares at A$10 (A$1,000) with A$10 brokerage, total cost is A$1,010. Cost basis per share is A$10.10. When selling, subtract brokerage from proceeds for net gain calculation.

Create a master position manager that includes all accounts. Tag each entry with account identifier. View positions individually by account (for tax) and consolidated (for total exposure). Spreadsheets can use filters; dedicated software usually handles this automatically.

Total Cost = (Old Shares × Old Cost) + (New Shares × New Cost) + Brokerage. New Average = Total Cost / Total Shares. Example: 100 shares at A$10 (A$1,000), add 50 shares at A$12 (A$600) + A$10 brokerage. Total cost A$1,610 / 150 shares = A$10.73 average.

In a split, quantity increases but cost basis per share decreases proportionally. For 2-for-1 split: 100 shares at A$20 cost becomes 200 shares at A$10 cost. Total cost remains A$2,000. Position manager must adjust quantity and per-share cost.

Record mental stops in your position manager with a flag indicating they are not live orders. Set alerts to notify when price approaches stop level. Mental stops require discipline to execute - the position manager alert reminds you but cannot force action.

Track each purchase as a separate lot with its own entry date, price, and quantity. When selling partial positions, select which specific lots to sell (usually highest cost or CGT-discount eligible). Document your selection for ATO purposes. Position manager should support lot-level tracking.

For each options position, calculate or obtain Greeks (delta, gamma, theta, vega). Sum each Greek across all positions for portfolio totals. Include underlying shares in delta calculation (shares have delta of 1). Display both position-level and portfolio-level Greeks.

Use broker API to fetch current positions. Compare against your position manager records. Identify differences: missing positions, quantity mismatches, incorrect costs. Flag for investigation. IBKR API supports this well. Other brokers may require CSV export/import.

Demergers split cost basis proportionally across the new entities. Follow ATO guidance or company announcements for allocation percentages. Update position manager: original position cost reduced, new position created with allocated cost. Total cost remains unchanged, just split.