Will your pension last your lifetime?

This longevity can create both opportunity and complexity. Strategies that once focused on 20 years of post-retirement spending may be insufficient when 30-40 years is becoming increasingly realistic. This makes longevity risk, the risk of outliving your assets, a central concern for people.

Beyond the 4% rule: Cash flow planning

A commonly cited benchmark is the 4% rule, which assumes you can safely withdraw 4% of your portfolio annually for about 30 years.[5] However, if retirement lasts 40 years or more, the maths is less reliable.

This is where cash flow modelling becomes important. Instead of relying on rules of thumb, financial advisers stress-test your finances under multiple scenarios: market downturns, inflation spikes, healthcare costs, tax changes, or unexpected family obligations. A simple cash flow plan may look similar to the image below:

The goal isn’t just to avoid running out of money, it’s to optimise the timing and sourcing of withdrawals across pensions, ISAs, investment portfolios, and other structures for maximum efficiency.

Pension calculators can also play a useful role by offering a starting point to model future income needs and compare them against current savings and investment strategies.

For those seeking more tailored insight, our pension calculator goes a step further. In addition to generating a personalised projection based on your income needs, lifestyle expectations, and retirement horizon, our pension calculator also draws on data from the Saltus Wealth Index, a biannual survey of over 2,000 individuals with £250,000 or more in investable assets. This provides a unique benchmark against others in a similar financial position. This includes insights into average pension pot sizes, contribution levels, and expectations around retirement, helping you see how your plans compare.

How much is “enough”?

To understand whether your pension will last your lifetime, you also need to work out how much you think you will spend. The Pensions and Lifetime Savings Association (PLSA) suggests that a “comfortable” retirement requires about £60,600 for a couple and £43,900 for a single person (as of 2025/26). While helpful as a general benchmark, these figures often fall short of what many individuals actually expect or need to maintain their desired lifestyle.

According to the Saltus Wealth Index Report, 60% believe they will need over £50,000 annually in retirement, regardless of marital status. Notably, more than 1 in 5 anticipate needing over £70,000 per year.[6]

Once things such as lifestyle inflation, private education for grandchildren, intergenerational gifting, and legacy planning are factored in, it’s not unusual to see cash flow requirements become much higher. Unlike the broader population, where state pension and annuities often form the backbone of retirement income, individuals with larger estates will typically rely more on drawdown from capital, which can bring additional complexity.

Beyond pensions: the full picture

Your pension is just one piece of the puzzle. Retirement income may also flow from the State Pension, ISAs, investment portfolios, property, or more advanced structures such as offshore bonds, trusts, or family investment companies.

These tools can be powerful but are technical and best considered with professional advice. The real advantage comes not from holding them individually, but from coordinating them. Aligning income sources across different wrappers allows you to manage tax, protect capital, and keep your plan aligned with both lifestyle and legacy goals.

Flexibility: Your most valuable asset

Over a retirement that could span four decades, conditions will change: markets, tax rules, spending patterns, and personal priorities. The best strategies are those built for flexibility.

That means being able to adjust withdrawal rates, shift asset allocations, or rethink the timing of gifts and transfers without jeopardising long term security. Scenario planning and cash flow modelling can provide the framework to adapt as life evolves.

Lifestyle, longevity, legacy

For wealthier individuals, retirement is rarely just about maintaining living standards. It is about balancing three goals:

• Preserving lifestyle
• Protecting longevity
• Planning legacy

Efficient wealth transfer strategies, from lifetime gifting to trusts or family investment companies, can reduce inheritance tax while keeping assets aligned to your values. Whether supporting children and grandchildren, funding charitable causes, or establishing philanthropic vehicles, wealth can be deployed purposefully while ensuring your own security. A financial adviser can support you to achieve your retirement goals in the most tax efficient manner possible.

The forward-looking question

Life expectancy is rising, and wealth strategies must rise with it. A plan designed for a 20 year retirement may not withstand 40 years of change.

The next step is clear: review your strategy, stress-test it against multiple scenarios, and ensure it reflects not only your lifestyle ambitions but also your legacy intentions. With the right planning, and the right financial adviser, you can be confident your wealth will last the distance, wherever the finish line may lie.