Ever opened your stocks and shares ISA statement and wondered how you stack up against people your own age? I have. More than once. That quiet curiosity often turns into a sharper question: am I on track, or am I lagging behind without realising it? The numbers that have recently come to light offer a clearer picture than most of us usually get, and they reveal something interesting. Average balances climb steadily with age, yet the way people actually invest changes just as much as the size of the pot.
What The Latest Figures Show About Stocks And Shares ISAs Across Age Groups
Fresh data paints a straightforward story. The average market value of a stocks and shares ISA rises with each successive age band. Under-25s sit at the bottom of the scale with a mean of £18,240. Those aged 25 to 34 hold around £41,060. The jump continues through the mid-life years, reaching £68,500 for 35-to-44-year-olds and £116,420 for those between 45 and 54. By 55 to 64 the average climbs to £150,990. It keeps growing after that: £176,600 for 65-to-74-year-olds, £204,870 for 75-to-84-year-olds, and £227,250 for people aged 85 and over.
These are means rather than medians, so a handful of large accounts can pull the figures upward. Still, the overall pattern is hard to ignore. Time in the market, higher earnings later in careers, and the simple power of compounding all play their part. I’ve found that looking at these numbers without context can leave people either reassured or quietly panicked. The real value lies in understanding why the averages move the way they do and how investment behaviour shifts alongside them.
| Age Group | Mean Market Value |
| Under 25 | £18,240 |
| 25-34 | £41,060 |
| 35-44 | £68,500 |
| 45-54 | £116,420 |
| 55-64 | £150,990 |
| 65-74 | £176,600 |
| 75-84 | £204,870 |
| 85 and over | £227,250 |
Seeing the progression laid out like this makes one thing obvious. Most people do not start with large sums. They build them. The early years often involve smaller contributions squeezed around other priorities such as housing costs, student debt or simply the higher relative cost of living when salaries are lower. Later decades bring more disposable income and, crucially, more years for earlier investments to grow.
Why Balances Tend To Grow With Age
Two forces dominate. First, earnings usually rise through the working years. Higher pay leaves more room for regular ISA contributions once the basics are covered. Second, the longer money stays invested, the more opportunity it has to compound. A portfolio that began modestly in someone’s twenties can look very different by the time that person reaches their fifties or sixties, provided they stayed the course through market ups and downs.
There is also a behavioural element. People who have held investments for decades often develop a stronger habit of adding to them. They may also become more comfortable leaving gains alone rather than taking profits at every opportunity. In my experience, the investors who reach the higher average balances are rarely those who made one spectacular call. They are the ones who kept contributing and let time do a large share of the work.
Of course averages hide variation. Some people in their thirties already hold substantial portfolios. Others in their sixties have far less than the mean. Life events, career paths, inheritance, and pure luck all create wide spreads within each age band. The published figures simply show the centre of the distribution.
How Investment Preferences Shift Across The Decades
The size of the pot is only half the story. What people actually put their money into also changes with age. Platform data shows a clear tilt. Younger investors lean heavily toward exchange-traded funds and tracker funds. Roughly seven in ten holders of these products are under 55. Only a small percentage of those aged 75 and over use them as a core holding.
That preference makes sense. When retirement sits decades away, the priority is usually long-term growth. Global equities, delivered through low-cost trackers, offer broad exposure without the need to pick individual companies. Market dips feel less permanent when there is time to recover. Simpler products also lower the barrier for people who are still building their knowledge and confidence.
Investors in their thirties, forties and early fifties show another pattern. They account for a large share of those holding overseas shares. Nearly half of such holdings sit with people aged 35 to 54. This may reflect more established portfolios and a greater willingness to look beyond domestic markets for companies and sectors that are under-represented at home. International diversification becomes easier once the basics of regular investing are already in place.
Later in life the picture changes again. Gilt and cash ISA holders skew older. Around two-fifths of them fall into the 55-to-74 bracket. Investment trust ownership also shifts upward. More than half of investment trust holders are aged 55 or over, and nearly one in five are 75 or older. Many of these trusts have long records of paying and growing dividends. Their closed-ended structure can give managers more flexibility to invest for the long term without the pressure of constant inflows and outflows.
Portfolios often evolve gradually, with growth assets, income-producing investments and lower-risk holdings playing different roles at different points in life. The key is keeping that balance matched to your goals, time horizon and attitude to risk.
That observation captures the practical reality better than any rigid age-based rule. People do not flip a switch on their sixtieth birthday and suddenly sell everything equities-related. Changes tend to be gradual. Some investors maintain a healthy equity allocation well into retirement because they still need growth to support a long retirement. Others start dialling risk down earlier because their circumstances demand greater predictability.
Younger Investors And The Growth Mindset
When the time horizon stretches twenty or thirty years, volatility becomes less threatening. A sharp market fall in year three of a thirty-year plan looks different from the same fall three years before retirement. Younger investors can therefore afford to keep a higher proportion of their stocks and shares ISA in growth-oriented assets. Global equity trackers and low-cost ETFs fit that need efficiently.
There is another practical advantage. These products are straightforward to understand and cheap to hold. That combination helps people start and, more importantly, stick with the habit of regular investing. I have noticed that the investors who build the largest pots later are often those who made contributing feel almost automatic in their earlier years. Complexity can wait. Consistency cannot.
This does not mean younger people should ignore risk entirely. Concentration in a handful of trendy shares can still derail progress. Broad diversification through trackers reduces the chance that one poor choice damages the whole portfolio. It also frees mental energy for the more important decision: how much to add each month.
Mid-Life Adjustments And Broader Horizons
By the time many people reach their thirties and forties, careers are more established and disposable income is often higher. Portfolios have had time to grow. At this stage some investors begin looking further afield. Overseas shares become more common. The UK market, while solid in certain sectors, does not offer the same breadth of technology, healthcare or consumer opportunities found elsewhere. Adding international exposure can improve long-term growth potential and reduce dependence on any single economy.
Risk tolerance may still be high, but it is rarely as unconstrained as it was in the early twenties. Mortgage payments, childcare costs or simply the desire for greater stability start to influence decisions. Some investors begin introducing a modest allocation to bonds or multi-asset funds. Others keep the equity focus but become more selective about the regions and sectors they favour.
This middle period is often when people refine their approach rather than overhaul it. They may switch from pure trackers to a mix of trackers and a few carefully chosen active funds or trusts. The goal is usually the same: keep the growth engine running while gradually improving resilience.
Approaching Retirement And The Shift Toward Stability
As retirement moves from distant concept to near-term reality, priorities change. Protecting what has already been built becomes more important. Generating reliable income starts to matter alongside, or even above, pure capital growth. This is when gilts, cash ISAs and income-focused investment trusts tend to attract more attention.
The data reflects that shift. Older investors hold a higher proportion of these lower-volatility or income-producing assets. That does not mean equities disappear. Many people still need growth to combat inflation over a retirement that could last twenty or thirty years. The balance simply tilts. A portfolio that was eighty or ninety percent equities in the thirties might move toward sixty or seventy percent, with the remainder providing ballast and income.
Investment trusts often appeal at this stage because many have established records of paying and increasing dividends over long periods. Their structure allows managers to smooth income by retaining some earnings in good years and using reserves in leaner ones. For someone planning to draw from their stocks and shares ISA in retirement, that consistency can feel reassuring.
Cash and short-dated gilts serve a different purpose. They provide a buffer against sequence-of-returns risk—the danger that a large market fall early in retirement forces the sale of assets at depressed prices. Having some capital that is less sensitive to equity markets can reduce the need to sell shares when they are down.
Why One-Size-Fits-All Rules Fall Short
It is tempting to turn age-based averages into rigid guidelines. Younger people should hold mostly equities. Older people should hold mostly bonds. Reality is messier. Personal circumstances matter far more than chronological age. Someone who inherits a large sum at thirty may already have a portfolio that looks like the average for someone twenty years older. A person who starts saving seriously only in their forties may still need a growth-heavy allocation in their sixties.
Attitude to risk also varies widely within any age group. Some sixty-year-olds sleep soundly with a high equity weighting. Others prefer the predictability of cash and bonds even if it means lower long-term returns. Goals differ too. One investor may plan to leave a substantial inheritance. Another may intend to spend most of the pot during their own lifetime. Those different objectives justify different asset mixes.
Perhaps the most interesting aspect is how portfolios evolve gradually rather than in dramatic shifts. People rarely sell everything and start again. They adjust contribution rates, rebalance occasionally, and slowly introduce new types of holdings as their needs change. The data simply captures the net result of thousands of individual decisions made over many years.
Practical Considerations For Building And Managing An ISA Across Life Stages
Start with what you can sustain. A smaller regular contribution that continues for decades usually beats a larger one that stops after a few years. Automation helps. Setting up a standing order or platform regular investment takes the decision out of monthly willpower.
Keep costs low, especially in the early years when the portfolio is still modest. Tracker funds and ETFs have made broad market exposure inexpensive. High fees compound just as powerfully as returns, but in the wrong direction.
Review the overall balance from time to time, not every week. Markets move. Life circumstances change. A quick annual check is often enough to decide whether the current mix still matches goals and time horizon. Rebalancing when one asset class has grown far beyond its target weight can keep risk in check without requiring constant attention.
Tax efficiency remains a quiet advantage of the stocks and shares ISA. Gains and dividends inside the wrapper are free of capital gains tax and income tax. That benefit compounds over long periods. Using the full annual allowance when possible accelerates progress, though it is not essential every year. Consistency matters more than perfection.
Diversification is not a slogan. Holding a mix of regions, sectors and asset types reduces the chance that any single event damages the entire portfolio. Global equity trackers provide a simple starting point. Adding bonds, property or other assets later can improve resilience without eliminating growth potential.
Common Pitfalls At Different Ages
Younger investors sometimes chase the latest hot sector or individual share. The excitement is understandable, yet concentration risk is real. A portfolio heavy in one theme can suffer lasting damage if that theme falls out of favour. Broad exposure first, selective tilts later, usually works better.
In mid-life the danger can be complacency or, conversely, over-trading after a strong run. Markets do not move in straight lines. Taking profits too early or abandoning a sensible plan after a short period of underperformance both undermine long-term results.
Closer to retirement, the opposite risk appears: becoming so defensive that the portfolio cannot keep pace with inflation. Cash feels safe in the short term, yet over a multi-decade retirement its purchasing power can erode significantly. A measured allocation to growth assets remains important for most people.
Another frequent misstep is treating the average for one’s age group as a target. The published figures are descriptive, not prescriptive. Falling short of the mean does not automatically signal failure. Exceeding it does not guarantee future security. Personal goals and cash-flow needs matter more than ranking against a statistical average.
Building Habits That Support Long-Term Progress
The investors who reach the higher end of the age-based averages rarely relied on one brilliant decision. They built habits. Regular contributions. Resistance to selling during downturns. Occasional rebalancing. A willingness to keep learning without constantly tinkering.
Those habits are available at any age. Starting later simply means the contributions may need to be larger or the time horizon adjusted. Starting earlier gives compounding more years to work, but it is never too late to begin or to improve an existing approach.
Clarity about goals helps. Someone saving primarily for retirement will make different choices from someone who may need access to capital in five or ten years. Writing down the purpose of the ISA and the rough time frame for drawing from it provides a reference point when markets become noisy or when new products appear attractive.
Attitude to risk is personal and can shift over time. What felt comfortable at thirty may feel different at fifty, and that is fine. The important part is aligning the portfolio with the current reality rather than with an outdated self-image.
Looking Ahead Without Rigid Rules
The data on average stocks and shares ISA values by age offers a useful benchmark. It shows that balances tend to grow with time and that investment preferences evolve as life stages change. Younger investors favour growth-oriented, low-cost products. Older investors place greater weight on income and stability. Neither approach is inherently superior. Each reflects different needs and time horizons.
What the numbers cannot capture is the individual story behind every account. Some people build substantial wealth through steady contributions and patience. Others experience setbacks that keep balances lower. Inheritance, career changes, health issues and pure luck all leave their mark. The averages simply describe the centre of a wide distribution.
In the end the most practical takeaway is straightforward. Match the mix of assets to personal goals, time horizon and genuine attitude to risk. Review that mix occasionally as circumstances change. Keep contributing when possible. Let time and compounding do a meaningful share of the heavy lifting. The path is rarely linear, yet the direction of travel for most long-term investors remains upward.
I still check the age-based figures from time to time, more out of curiosity than judgement. They remind me that progress is usually measured in years and decades rather than months. They also underline that the “right” portfolio is the one that fits the life being lived, not the one that matches a statistical average. That perspective has proved more useful than any single number.
Building a stocks and shares ISA is less about hitting a particular average at a particular age and more about creating a process that can adapt as life unfolds. The figures provide context. The real work happens in the choices made month after month, year after year. Those choices, more than any snapshot of current balances, determine where the portfolio stands when it is finally needed.
