TSP Annuity Calculator: Maximize Your Retirement Plan

This tool calculates your annuity payments from your TSP contributions to help you plan your retirement finances.

How to Use the TSP Annuity Calculator

To use this calculator, simply fill out the initial balance, monthly contribution, expected annual growth rate, and the number of years you plan to invest. Once all the fields are filled, click on the “Calculate” button to see the projected balance of your savings.

Explanation of How It Works

This calculator uses the Future Value of an annuity formula. It considers your initial balance, the monthly contributions, and the growth rate to calculate your total savings at the end of the investment period. The formula used is:

FV = P * (1 + r/n)^(nt) + C * [((1 + r/n)^(nt) - 1) / (r/n)]


  • FV: Future Value
  • P: Initial Balance
  • r: Annual Growth Rate
  • n: Number of times interest is compounded per year (12 for monthly contributions)
  • t: Number of years
  • C: Monthly Contribution


This calculator is designed for educational purposes only. The actual performance of investments can vary significantly due to market conditions, fees, and other factors. Always consult with a financial advisor for precise investment planning.

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