Traditional TSP vs. Roth TSP Calculator
A powerful tool to help federal employees decide between pre-tax and after-tax retirement contributions. This traditional tsp vs roth tsp calculator projects your potential after-tax retirement funds.
Enter Your Financial Details
Your current age in years.
The age you plan to retire.
This helps estimate your current marginal tax rate.
Your total yearly income before taxes.
The total amount you plan to contribute each year.
Your estimated average annual return on TSP investments.
Your best guess for your marginal tax rate after retiring.
Key Values
Formula: Future Value = P * [(((1 + r)^n) – 1) / r], where P is annual contribution, r is rate, n is years.
Growth Comparison Over Time
| Year | Traditional TSP Balance (Pre-Tax) | Roth TSP Balance (Tax-Free) |
|---|
This table illustrates the projected growth of each account balance over your investment horizon.
This chart visually compares the projected after-tax values of a Traditional vs. Roth TSP at retirement.
Understanding the Traditional TSP vs. Roth TSP Calculator
What is the Traditional TSP vs. Roth TSP choice?
The choice between a Traditional Thrift Savings Plan (TSP) and a Roth TSP is a fundamental decision for federal employees planning for retirement. The core difference lies in when you pay income taxes. With a Traditional TSP, you contribute pre-tax dollars, which lowers your current taxable income and gives you an immediate tax break. Your money grows tax-deferred, and you pay taxes on withdrawals in retirement. Conversely, with a Roth TSP, you contribute after-tax dollars. There’s no upfront tax deduction, but your qualified withdrawals in retirement—both contributions and earnings—are completely tax-free. Our traditional tsp vs roth tsp calculator is designed to model these outcomes to help you make an informed choice.
Who Should Use This Calculator?
Any federal employee or uniformed service member eligible for the Thrift Savings Plan should use this traditional tsp vs roth tsp calculator. It is especially useful for:
- Younger employees who might be in a lower tax bracket now than they will be in retirement.
- High-income earners who want to analyze the benefits of a current tax deduction.
- Individuals planning their long-term tax strategy for retirement.
- Anyone confused about which TSP option better suits their financial goals.
Common Misconceptions
A frequent misunderstanding is that the account with the higher balance at retirement is always better. However, what truly matters is the after-tax amount you can spend. A million-dollar Traditional TSP balance is not the same as a million-dollar Roth TSP balance because the former is still subject to income tax. This traditional tsp vs roth tsp calculator focuses on the final, spendable amount.
Traditional TSP vs Roth TSP Calculator Formula and Explanation
The calculations involve projecting the future value of your investments and then adjusting for taxes. The traditional tsp vs roth tsp calculator uses the standard future value of an annuity formula.
Step 1: Calculate Years of Growth. This is simply the difference between your retirement age and current age.
Step 2: Calculate Future Value (Pre-Tax). The formula is: FV = P * [((1 + r)^n - 1) / r], where:
- FV = Future Value of the account.
- P = Annual Contribution. For the Roth TSP, this is the after-tax contribution amount.
- r = Expected Annual Investment Growth Rate.
- n = Number of Years of Growth.
Step 3: Determine After-Tax Value.
- For Traditional TSP: The after-tax value is `FV * (1 – Retirement Tax Rate)`.
- For Roth TSP: The after-tax value is simply the `FV`, as qualified withdrawals are tax-free.
Variables Table
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| Current Income | Your gross annual salary | Dollars ($) | $40,000 – $180,000+ |
| Annual Contribution | Amount invested in TSP per year | Dollars ($) | $1,000 – $23,000+ |
| Growth Rate | Annualized return on investments | Percent (%) | 4% – 10% |
| Current Tax Rate | Your current marginal federal tax rate | Percent (%) | 12% – 37% |
| Retirement Tax Rate | Your expected marginal tax rate in retirement | Percent (%) | 10% – 35% |
Practical Examples (Real-World Use Cases)
Example 1: Early-Career Employee
An employee is 25, earns $60,000/year (22% tax bracket), and plans to retire at 65. They contribute $8,000 annually, expect a 7% growth rate, and believe their retirement tax rate will be 24%. The traditional tsp vs roth tsp calculator shows that the Roth TSP is likely better, as they pay taxes now at a lower rate (22%) and avoid a higher rate (24%) on a much larger balance in the future.
Example 2: Peak-Earning Employee
An employee is 50, earns $150,000/year (24% tax bracket), and plans to retire at 65. They contribute $20,000 annually, expect a 6% growth rate, and anticipate their retirement income will place them in a lower 22% tax bracket. In this scenario, the traditional tsp vs roth tsp calculator would likely favor the Traditional TSP. The immediate tax deduction at a 24% rate is more valuable than paying that rate now to save 22% later.
How to Use This Traditional TSP vs Roth TSP Calculator
- Enter Personal Data: Input your current age and planned retirement age.
- Input Financials: Provide your current gross income, tax filing status, and how much you plan to contribute to your TSP annually.
- Set Assumptions: Enter your estimated annual investment return and what you predict your marginal tax rate will be during retirement. This is a key variable.
- Review the Results: The calculator will immediately display which option provides a higher after-tax retirement fund. It will show the primary result, key values like total future value, and your estimated current tax rate.
- Analyze the Chart and Table: Use the dynamic chart and year-by-year table to visualize the growth of each account over your career. This helps understand the long-term impact of your choice.
Key Factors That Affect Traditional TSP vs Roth TSP Results
The output of any traditional tsp vs roth tsp calculator is highly sensitive to your inputs. Here are the most critical factors:
- Your Current vs. Future Tax Rate: This is the most important factor. If you expect your tax rate to be higher in retirement, the Roth TSP is generally better. If you expect it to be lower, the Traditional TSP is often favored.
- Investment Time Horizon: A longer time until retirement means more years for tax-free growth in a Roth TSP to compound, often making it more powerful.
- Expected Rate of Return: Higher growth rates amplify the benefit of tax-free earnings in a Roth TSP.
- Annual Contribution Amount: Maximizing contributions gives you a larger base for growth in either account.
- Income Phase-Outs (for IRAs): While the Roth TSP has no income limits to contribute, Roth IRAs do. This makes the Roth TSP a valuable tool for high-income federal employees. See our guide on Roth IRA Contribution Limits for more.
- Agency Matching Contributions: Remember that all agency/service matching contributions are automatically deposited into your Traditional TSP balance, regardless of your choice. This is a key part of using a traditional tsp vs roth tsp calculator accurately.
Frequently Asked Questions (FAQ)
1. Which TSP is better if I expect tax rates to go up in the future?
If you believe federal income tax rates will be higher across the board in the future, the Roth TSP is generally more advantageous. By paying taxes now, you lock in today’s rates and protect your future growth from potentially higher taxes.
2. Can I split my contributions between Traditional and Roth TSP?
Yes, you can. This is a popular strategy to diversify your tax risk. You can allocate a percentage of your contributions to both, giving you a mix of tax-deferred and tax-free funds in retirement.
3. What happens to my agency match if I contribute to the Roth TSP?
All agency automatic (1%) and matching contributions are always made to your Traditional TSP balance, even if you contribute 100% to your Roth TSP. Our traditional tsp vs roth tsp calculator considers only your own contributions.
4. Are withdrawals from a Roth TSP always tax-free?
For withdrawals to be “qualified” (and thus tax-free), you must be at least 59½ years old (or meet other specific conditions) AND it must have been at least five years since January 1 of the year you made your first Roth TSP contribution.
5. Does this traditional tsp vs roth tsp calculator account for state taxes?
This calculator focuses on federal taxes, which is the primary driver of the decision. State tax treatment of retirement income varies significantly. You should consider your current and future state of residence as an additional factor.
6. What if my income is too high for a Roth IRA?
The Roth TSP has no income limitations, making it an excellent tool for high-income federal employees who are phased out of contributing to a Roth IRA. This is a significant advantage of the TSP.
7. How does the traditional tsp vs roth tsp calculator estimate my current tax rate?
The calculator uses the provided income and filing status to find your marginal tax bracket based on current IRS figures. This provides a reasonable estimate for the value of the Traditional TSP’s tax deduction.
8. Why is predicting my retirement tax rate so hard?
It’s difficult because it depends on your future income sources (pension, Social Security, other investments), your withdrawal strategy, and what tax laws will look like in 10, 20, or 30 years. Using the traditional tsp vs roth tsp calculator with different rate assumptions can help you see a range of possibilities.