Try Out MTM’s Retirement Calculator!


Already know how the calculator works? Great!

Click here to try out the MTM Retirement Survival Calculator now!


How It Works

This calculator attempts to answer the question ‘How much do I need to retire?’ .


The generally accepted rule of thumb is that individuals looking to retire should amass at least 25 times their annual expenses (AKA the 4% rule)  in order to have a fruitful retirement. The idea being that you can safely withdraw this amount each year while adjusting for inflation and riding whatever the market throws at you.


But the problem with rules of thumb is that they do not paint a granular enough picture.


Take a look at the following example:

  • Anna retired in 1968 with a retirement pot worth £750K and spends £30K per year
  • Barry retired in 1974 with a retirement pot worth £750K and spends £30K per year
  • Carly retired in 1977 with a retirement pot worth £750K and spends £30K per year

Now, all three of these individuals have followed the 4% rule of thumb and began retirement with 25X their annual expenses. In fact the only difference between them is the start date of their retirement, and yet below are the results of how they would have fared forty years on from their respective retirement dates.



Anna ended up with a dismal -£113K after 40 years – so much for the rule of thumb in her case. Meanwhile, Barry laughed himself into old age with over £1.9M, and Carly ended up somewhere in the middle with £740K.


MTM’s Retirement Survival Calculator can show what you would have needed in the bank to ensure you didn’t exhaust your portfolio in retirement. How? By showing you exactly how your money would have kept you going during various 40 year periods in the past.

Remember, in retirement you are unlikely to have access to a regular income, so how would your portfolio have handled:

  • Stagflation in the 70s
  • Black Monday
  • The Credit Crunch

If you retired in 1962, what would have happened to you and your money after forty years of withdrawals? And then the same again for a retirement starting in 1963, and 1964 and so on; MTM’s retirement calculator can illustrate that hypothetical scenario for so you can see for yourself.


“Past performance is not indicative of future earnings”

No, it isn’t. But consider this:

Imagine, for a minute that you are packing for a holiday to go to Uganda. You’ve done your homework and you know that the lowest temperatures ever recorded at this time of year are circa 18°C. Now that doesn’t guarantee that it will never drop below that point in the future, but you can definitely make an informed decision on whether it’s worth packing a winter coat or not.

This is similar to how the calculator works. It won’t replace a competent Financial Planner, or sound due diligence on your part, or a whole host of other things you should do when considering retirement! But it helps illustrate a fraction of the answer to the age-old question, ‘How much do I need to retire?’.


Try out the retirement calculator!



  • The calculator assumes 0.18% in fees associated with managing the portfolio
  • That there are no fees/taxes concerned with withdrawing money from the pot
  • That individuals adjust their withdrawals in line with inflation
  • That individuals do not earn a single penny after their retirement date
  • That the retired individuals in will never adjust spending to ensure they have  a better chance of surviving.
  • That the allocation of the portfolio will never change


Inspired by FireCalc