Thinking of investing in an annuity plan is a good strategy for having sustainable funds in our retirement. But figuring out the withdrawal strategy can be overwhelming. WordLayouts’ Annuity Calculator helps you understand how your annuity grows and shrinks over time so you can make informed decisions.
Annuity Calculator
This Annuity Calculator is a preprogrammed Excel tool for anyone who wants to buy annuity plans or see how annuitization works. Once you set a capital base and choose your expected return rates, we tell you the exact dollar amount you can expect to receive during retirement, after adjusting for inflation. This spreadsheet comes with:
- A year-by-year schedule showing annuity payouts over time
- A Results section presenting key annuity planning metrics
- Visual aids for quick data-sharing.
A separate workbook lets you calculate backward from common retirement goals. So instead of guessing, you can confidently know “How long your savings will last?” or “How much do you need to invest today to retire comfortably?”
What this calculator does
This calculator helps you evaluate:
- The sustainability of your withdrawal plan
- The impact of inflation on income
- The effect of taxes on taxable brokerage accounts
- Longevity risk from age 65–95
- Early retirement viability
Before we explore the practical use of this calculator, let’s look at the type of financial product we are dealing with here.
What’s an Annuity?
A legal contract between you and an insurance company where you invest money with the insurer (during the accumulation phase) in exchange for a regular stream of income upon retirement (during the payout or annuitization phase). Annuities are designed to ensure a steady cash flow that can last for life.
Can I buy annuity plans right away?
Yes. You can buy annuities by making either a single payment or a series of payments, as in any savings or investment account.
Types of annuities
There are different types of annuity plans out there, such as these.
- Immediate Annuities: Payments start right away, that is, as soon as you buy the plan. Ideal for someone who just retired and wants a steady income starting today.
- Deferred Annuities: Payments start rolling at a later date. Most retirement annuity plans are deferred annuities. Often used by people in their 40s or 50s, saving for retirement income at 65.
- Indexed Annuities: Returns are tied to a market index, such as the S&P 500 or any other benchmark. This kind of plan aims to combine market-linked growth with some protection against losses.
Tax Benefits of Investing in an Annuity
Money that stays invested grows on a tax-deferred basis, so interest, dividends, and capital gains are not taxed annually. Instead, you pay taxes when you withdraw money during retirement.
What part is taxable?
In a non-qualified annuity (that is, outside a Traditional IRA or tax-deferred account), each payment or distribution consists of two parts:
- Principal (money you have invested)
- Earnings (returns on your investment)
During the accumulation phase, annuities follow LIFO taxation (Last In, First Out). That means if your annuity has grown, your early withdrawals are assumed to be coming from earnings first, which are taxable. The principal part is not taxed.
During the payout phase, the IRS calculates the taxable portion using an “exclusion ratio” to determine how much of each payment is treated as a return of principal (tax-free) versus taxable income.
Withdrawal penalties
Investment accounts are built to encourage returns. That’s why most annuities come with a surrender period of 5, 10, or more years, or why the IRS has a 59.5-year rule in the first place.
Can I withdraw money before retirement?
Technically, yes. But beware of withdrawal penalties. If you withdraw before the age of 59½:
- The IRS adds a 10% penalty on the taxable amount.
- This penalty is in addition to regular income tax.
A Step-by-Step User Guide for the Annuity Calculator
This annuity calculator template includes two powerful calculation sheets.
The first sheet provides a detailed year-by-year simulation of your withdrawals. It shows how your balance changes over time while accounting for factors such as variable investment returns, inflation adjustments, and taxes on interest. The sheet also includes charts that visually track your remaining balance, net payments, and interest earnings throughout the payout period.
The second sheet helps you quickly answer common annuity questions, such as how much starting capital you need to generate a specific annual income, how long a given balance will last with regular withdrawals, and how much you can safely withdraw each year based on your savings, interest rate, and inflation assumptions.
Now, let us look at them in detail.
Sheet 1: Annuity estimator
The first sheet is the forward-looking payout simulator. It models how a lump sum performs under different user assumptions, such as expected return rates, inflation rates, tax rates, and payment terms.
Let’s explore this section, one input at a time.
Input Table
1. Initial age
Choose when you plan to retire. This is when you start receiving annuity payments. The sheet uses Initial Age to align and project the yearly payout schedule below.
When Do Most Americans Retire?
There’s no exact answer to that question. Traditionally, the average American stops working at 65, which aligns with Medicare eligibility and most workplace pension programs. However, according to the SSA, the full retirement age (when you can collect full Social Security benefits) is 66 or 67 years old, depending on birth year.
2. Years to pay out
Specify the length of the withdrawal period. This is the total number of years you’ll receive payments.
When it comes to withdrawal plans, be realistic about life expectancy, which averages at 79.0 years for the US (as of 2023). However, many planners still use a higher age of 90–95 to reduce the risk of outliving retirement income.
3. Initial capital (principal)
The total amount of money invested or saved in your account when you hit retirement. This becomes the starting point of your Payout Schedule below!
If unsure, ask the insurance company for an estimate of what your retirement pool will look like when you retire, based on current contributions and assumed growth rates.
Keep in mind that if your annuity plan is funded with after-tax dollars, then the Principal portion of each payout that represents your original contributions is NOT taxed again. Only the earnings portion is subject to ordinary income tax.
Choose return assumptions
Specify the rate at which your savings earn interest every year. The sheet uses this % to gradually grow your invested money.
We offer two ways to calculate interest:
- Fixed: Interest calculator based on a constant or fixed rate. Choose this option in the dropdown when calculating interest on a fixed annuity, a Certificate of Deposit, or any other guaranteed income product.
- Variable: Interest calculated based on a safe, possible range of rates. Choose this option when returns depend on market performance and can move up or down each year.
Rate Randomization Feature
From a planning perspective, simple randomization is what makes this calculator more robust and practically useful. After all, market conditions or account rules change all the time. Plus, it’s simply good sense to prepare for the worst possible financial scenario you might have to tackle in the future.
For variable rates, enter a Minimum and Maximum rate to set the lower and upper bounds for rate simulation. The sheet then lands on a completely random rate that lies somewhere between the Min and Max rates.
Press F9 to generate a new set of random rates. This instantly updates the Average, giving you a sense of different possible outcomes for your retirement withdrawal plan.
Inflation Rate
Any retirement plan must account for inflation. Set higher or lower inflation rates to prepare yourself for the worst and best future scenarios. 2% to 3% is generally seen as a realistic estimate of how the economy behaves.
What is inflation?
Inflation refers to the loss of value (or purchasing power) of money over time. It is often modeled around 2% because the Federal Reserve strives for ~2% inflation long-term. Most inflation calculations rely on the Consumer Price Index (CPI) to estimate the impact of inflation on your money over time.
Tax on earned interest
In this field of the calculator, enter your expected income tax rate at the time of the withdrawal. In non-qualified annuities, contributions to your retirement account are made using after-tax dollars. Because you have already been taxed, your investments grow on a tax-deferred basis. That means when you withdraw, only the earnings portion is taxed. Your original contributions are not taxed again.
If modeling a traditional IRA, you may choose to enter 0% here and instead account for taxes separately when calculating withdrawals, since IRA distributions are generally fully taxable.
B) The Summary Section
Initial annual payment
This is the money you will receive in the first year of annuity payments. Based on user inputs, the sheet calculates the amount of money you withdraw in the first year before taxes and inflation adjustments.
Last annual payment
The final withdrawal amount at the end of the payout period. If you choose to factor in inflation, this amount will (naturally) be higher than the Initial Annual Payment.
Here’s why…
If inflation is applied in the model, each year’s withdrawal increases to maintain purchasing power. Because of this compounding effect, the last payment is usually higher than the first one when inflation adjustments are included. If inflation is not applied, the final payment remains the same as the initial withdrawal amount.
Total interest earned
The total amount of interest earned on your principal amount and prior interest. Taxes are not considered when calculating interest earnings. They are separately calculated in the cell below using the tax rate specified by the user earlier.
Graphs and Visualizations
To make the insights from your retirement planning actionable, we have three charts for you as well:
- Balance: Each bar represents your account balance over the annuitization period. As you withdraw more funds, the balance decreases over time.
- Net Payment: Net payment refers to your withdrawal amount after accounting for taxes. This graph shows your net payment across payout periods to help you evaluate whether your retirement income is still sustainable after accounting for taxes.
- Interest: Visually map out your interest earnings over time until the last payout. This makes it easier to understand when growth accelerates and how interest contributes to your final payout amount.
Payout Schedule
Right below, the calculator offers a year-by-year payout schedule, showing account metrics at each point of withdrawal.
Here’s what each column shows (B to J):
- Year—Payout year number.
- Age—Your age that year.
- Interest Rate—Annual growth rate applied, based on user input above.
- Interest Pre-Tax—Earnings before taxes.
- Tax—Taxes owed on earnings.
- Withdrawal—Total amount withdrawn.
- Net Payment—Withdrawal amount after taxes.
- Balance—Remaining account value.
- Cumulative Interest—Total interest earned so far.
This projection shows you how your annuity depletes over the retirement period while earning interest and how taxes impact your actual income at each stage.
This example shows a fixed 7% interest rate, which is why the balance depletes predictably to zero by year 30. With a variable rate, the final balance depends on actual market performance—it could be higher or lower
Each time you adjust values in the input panel above, make sure to review the yearly payout schedule to see how your periodic metrics and account totals change in response.
Sheet 2: Annuity Calculator
This is a reverse-engineering sheet. Each table on the right solves for key annuity planning metrics, such as required principal amount, required years, and annuity payment amount.
These tables help you find answers to:
- How much do I need to retire?
- How long will my money last?
Solve for principal
Suppose you want an annual retirement income of $60,000. What amount of starting capital will you need to make that happen?
Let’s find out.
To solve for principal, manually enter the following information first:
- Annual Payment: The fixed withdrawal you plan to receive each year.
- Interest Rate: The annual growth rate or return you expect on the remaining balance.
- Inflation Rate: The yearly percentage increase in the withdrawal to maintain purchasing power.
- Years to Withdraw: How many years you’ll receive payments.
- Annual Payment Terms: Whether payments occur at the beginning or end of each year. This dropdown changes the mathematical structure of the annuity as it determines when withdrawals occur relative to investment growth. That timing difference materially affects sustainability, total interest earned, and final account balance.
Based on these inputs, the sheet calculates the initial amount of investment you need to secure that target income stream over your chosen withdrawal period.
Solve for Years
Timelines are a key metric of retirement planning. Let’s say you plan to spend $80,000 every year in retirement; how long will your money last?
This is a useful tool for early retirees, who can precisely project payout timelines based on different assumptions, such as:
- Initial Principal: Estimate the amount of money you already have saved or invested.
- First Annual Withdrawal: Determine the amount you plan to withdraw in the first year.
- Interest Rate: Define the expected annual return on your remaining balance.
- Inflation Rate: Set the yearly rate by which withdrawals will increase.
- Annuity Payment Term: Choose whether withdrawals are made at the start or end of each year.
Remember, over long horizons, even a small timing assumption can change sustainability by several years. For example, if you withdraw $60,000 at the beginning of the year instead of the end, that $60,000 never earns a year of return. The difference compounds over 20–30 years, with the gap becoming significant over long time horizons.
Solve for Annuity Payment
Think of this table as a summarized version of the first sheet. It helps you calculate how much regular annuity payment you can safely withdraw from your retirement account for a fixed period.
Once you enter the initial principal and expected interest/inflation rates and specify how long you want to receive payment, the sheet calculates your first and last annual payment.
We also adjust for inflation to reflect rising living costs and preserve purchasing power throughout the payout period.
Comparison Table
At the heart of this sheet is a comparison table showing three retirement payout scenarios side by side. This way, you can evaluate trade-offs between principal, withdrawal amount, and longevity in a clean, readable format.
Column 1 – Required starting capital
This column shows how much money you would need at the beginning if you want to withdraw $25,000 per year for 25 years, assuming a 6% return and 2% inflation.
The calculator estimates that you would need about $338,758.94 to support those withdrawals. When adjusted for inflation, the equivalent value is $409,253.45.
Column 2 – How long the money will last
This scenario starts with $1,000,000 and assumes annual withdrawals of $70,000. With a 6% return, the funds would last approximately 28.38 years. The table also shows the inflation-adjusted principal to illustrate how the value changes when accounting for inflation.
Column 3 – Maximum sustainable withdrawal
In this scenario, you begin with $1,000,000 and plan to withdraw money over 20 years. Based on the same 6% interest rate, the calculator estimates an annual withdrawal of about $82,249.58.
This Comparison Table gives a simple overview of different retirement income strategies and helps understand how changes in savings, withdrawal amounts, or time horizons affect the results.
Visual Elements
The same information is also highlighted using graphic illustrations (a bar chart and a donut chart) to see the key results of the annuity calculations. The bar chart lets you compare how much Principal amount you would need for different scenarios. The Donut Chart compares the years to withdraw to show how long the funds will last under different scenarios.
Here are some scenario-testing ideas for quick inspiration:
- What principal do I need to fund $25k per year for 25 years?
- If I have $1M and withdraw $70k annually, how long will it last?
- If I want the money to last exactly 20 years, how much can I withdraw?
How to Review an Annuity Contract Before You Invest
Carefully read and review the materials given to you (such as the annuity contract, prospectus, etc.). Consult a financial professional if there’s anything you don’t understand.
For example, you might want to inquire about any fees (upfront, surrender, ongoing, or implicit) or other limits on investment performance to help accurately estimate your net returns.
Learn more about annuity contracts in the US on the official Securities and Exchange Commission website right here!
Key Benefits of Investing in Annuity Plans
Annuity plans are perfect if you received a large lump sum of money, such as a settlement, a lottery win, or an inheritance, and want to set it aside for later years.
If you want a stable, guaranteed income during retirement years, annuities are a reliable investment in the long run. On the other hand, annuities are generally not suitable for those with high liquidity needs.
Did You Know? Only natural persons can benefit from annuity plans. A company, organization, or trust cannot be an annuitant.
Limitations and Disclaimers
This calculator is for illustrative and planning purposes only. It is not a full-time retirement planner, as it does not account for all possible variables that can affect annuity payments and timelines in real life. For example, the sheet doesn’t consider the impact of Social Security, Medicare premiums, RMDs, fees, or expense ratios, or any risks associated with market volatility. These factors can significantly affect your account totals, including your total account balance, returns, and payout timelines.
The sheet only uses simplified tax modeling by applying a flat tax to interest. Real U.S. taxation is more complex and may be subject to specific federal or state tax rules.
What we assume
- Returns on investment are modeled on a single blended rate, regardless of your account portfolio
- That inflation remains constant, even though real-world inflation can vary from year to year
Who Can Benefit from The Annuity Calculator
This calculator is a quick and handy resource for:
- DIY retirement planners in the U.S.
- Financial advisors are doing preliminary modeling
- Pre-retirees age 45–65
- Individuals evaluating annuity-style withdrawals
- People comparing fixed annuities vs. self-managed withdrawal
Note for Excel Beginners
This calculator was programmed on a standard Excel Open XML workbook (.xlsx). Because it’s .xlsx, it’s also VBA-free. So there is no “macro compatibility” issue.
Works on most modern versions of Excel, including…
- Microsoft Excel 2007 and newer (Windows)
- Microsoft Excel 2008 and newer (Mac)
- Does not natively work in the Excel 2003 version and older
Employs basic Excel functions, such as…
- Built-in formulas
- Data validation dropdowns
- Conditional formatting
- Named ranges
Good news: Most of these functions are supported in Google Sheets! Although specific functions may behave differently and need slight adjustments to work as intended.
All cells showing automatically calculated values are locked to keep formulas intact. Don’t type over these.
How to Fix Broken Formulas in Excel
Spreadsheets are fragile. Even if the file works perfectly when you download it, accidental changes can break formulas or throw off formatting. Use this template only if you’re comfortable with Excel and able to spot and fix formula or input issues.
For specific instructions, read Microsoft’s official guide on How to avoid broken formulas in Excel.
