My wife and I plan to retire at different times. How do we find our ‘magic’ retirement number? 

Have a question about your own retirement savings? Email us at HelpMeRetire@marketwatch.com

Dear Reader, 

Having a number in mind can help for saving purposes, but first be aware that this figure can fluctuate in any given year — before and during retirement — so don’t lock yourself into it. 

That said, this will all come down to your income needs in retirement. The difference in retirement dates will affect what money you’re bringing in (and thus, how much you’re withdrawing from your retirement accounts), but the amount of money you’ll need in retirement will likely stay the same between both retirement years (unless a major life event occurs, like a medical emergency or a change in residence). 

A qualified financial planner can get into the minute details associated with having two separate retirement ages. They often use software, input all the factors along with inflation and assumed rates of return on investments, and they can pull significant data to assess and put into plans. An online calculator will give you an idea of what you should be putting away in order to have enough for the future, but they won’t be nearly as granular as what a professional can do. 

MarketWatch’s retirement calculator

Still, they can be useful tools to get an idea of what you’ll need. MarketWatch actually has a very comprehensive retirement calculator. Check it out here.

Before I explain how it works, let me be very clear. These tools should solely be used as a starting point — the outcome is not set in stone. There are far too many variables that can and will change between now and when you retire, and thereafter, so run the numbers regularly — once a year at least, or every six months if you’re closer to retirement — to make sure you’re still on track. 

Lastly, the output is only as good as the input. If you put unreasonable assumptions into the calculator, or miss big figures like a mortgage or a forgotten 401(k), your answers won’t make sense. 

Back to the MarketWatch visual planner. Start at the top with your current ages and your estimated retirement ages. Input your salaries and any amount you save. 

Then work on the more specific details. Under held assets, click an asset type from the drop down menu and input details — if, for example, you have home equity or a 401(k) plan, with or without an employer match.

Under future income, choose to include Social Security or not, but if you do, review the estimates and adjust them based on what you think you’ll actually get. If you have an account with the Social Security Administration online, get their estimates for your benefits at various claiming ages. (If you don’t have an online account, set one up immediately.) Under this section, add assets like an expected lump sum amount or a pension. 

Retirement spending

The retirement spending category lets you see some of the major expenses, including healthcare and transportation. With “advanced settings” input figures for life expectancy, expected annual raises, and tax rates. It even has inflation rates for various spending categories, and if you want to be extra cautious, bump that number up for medical costs. 

That tool that can help you, but again, don’t rely on it. Focus also on what you can do now to provide your future self with financial security. Remember to save regularly, and review your current expenses with your wife so that you’re aligned now and on your plans for the future. 

When something big happens in your lives, go back to the budgets and the retirement plans and adjust accordingly. Look at your asset allocation within your investment portfolios, and check those regularly to make sure they haven’t veered off course because of market moves. And be flexible.

The retirement saving process is long, and it has a few twists and turns along the way, but it’s absolutely worth it to be as diligent as it appears you want to be.