There’s no single right figure. A common rule of thumb is to put 10–15% of your income towards long-term goals, including pension contributions. Start with whatever you can sustain, even £50 a month, once you have an emergency fund and expensive debt cleared. Consistency matters far more than the amount you begin with.
The short answer
- Aim for around 10–15% of gross income towards long-term goals, including your pension.
- Secure an emergency fund and clear expensive debt before you start investing.
- Capture any employer pension match first: it is effectively free money.
It is a deceptively simple question with no single answer, because the ‘right’ monthly amount depends on your income, your goals and how much you already have working for you. The good news is that the exact figure matters far less than most people fear, starting at all, and keeping it up, does most of the work. Our beginner’s guide to investing walks through the foundations; here is how to land on a number you can actually live with.
A sensible starting point
A widely used rule of thumb is to channel around 10% to 15% of your gross income towards long-term goals, and crucially, your pension counts. For most employees, workplace pension contributions already make up a chunk of that, so the question becomes how much to add on top through an ISA or other investments. If 15% feels out of reach today, that is fine: the target is a direction of travel, not a threshold you must clear immediately.
Before you commit anything to the market, make sure two foundations are in place. First, an emergency fund of roughly three to six months’ essential spending, held in easy-access cash, so an unexpected bill never forces you to sell investments at a bad time. Second, clear any expensive debt such as credit cards, where the interest almost certainly outweighs any return you could expect to earn. With those covered, whatever you can sustainably spare each month can go to work.
Small amounts add up
Do not dismiss modest contributions. Because returns compound, your growth earns growth of its own, even £50 or £100 a month can build into a meaningful pot over the decades. The table below shows, purely for illustration, how regular monthly investing might grow at an assumed 5% annual return after charges. Real returns will vary and are not guaranteed, but the shape of the thing is what matters.
How regular monthly investing can grow (illustrative, 5% a year after charges)
| Monthly amount | After 10 years | After 20 years | After 30 years |
|---|---|---|---|
| £50 | ≈ £7,800 | ≈ £20,500 | ≈ £41,000 |
| £100 | ≈ £15,500 | ≈ £41,000 | ≈ £82,000 |
| £250 | ≈ £38,800 | ≈ £102,000 | ≈ £205,000 |
| £500 | ≈ £77,600 | ≈ £205,000 | ≈ £410,000 |
The striking thing about those columns is how the later decades dwarf the early ones. Most of the final figure comes not from the money you paid in but from growth on growth, which is exactly why when you start tends to matter more than how much. A smaller sum invested in your twenties can end up beating a larger sum started in your forties.

Match the amount to your goal
If you have a specific target, a house deposit in ten years, or a certain retirement pot, you can work backwards to a monthly figure rather than pluck one from the air. Decide roughly how much you want and by when, make a cautious assumption about growth, and a simple online compound-interest calculator will tell you the monthly contribution required. It is far more motivating to invest £180 a month towards a defined £30,000 deposit than to save a vague ‘whatever is left’, and it lets you sense-check whether your timescale is realistic or needs stretching.
Remember, too, that different goals suit different accounts. Long-term retirement money is usually best going into a pension for the tax relief; medium-term goals of five years or more fit neatly inside a stocks and shares ISA; and anything you might need within five years generally belongs in cash rather than invested at all. Sorting your monthly contributions by goal, not just by amount, keeps each pot in the right home.
Building your own number
- 1
Secure the foundations first
Hold three to six months of spending in cash and clear expensive debt before investing a penny.
- 2
Capture free money
Contribute enough to your workplace pension to earn the full employer match: it is an instant, guaranteed return.
- 3
Set a percentage, not just a figure
Aim towards 10–15% of income across pension and investments, then automate it so it happens without thought.
- 4
Increase it over time
Nudge your contribution up whenever you get a pay rise, so investing grows with your income painlessly.
Automating the payment for the day after payday is the single most effective trick: money you never see is money you never miss. Start with a figure that is comfortable rather than heroic, a plan you keep going for twenty years beats an ambitious one you abandon after three. If you would like help setting a target around your wider goals, our free service can match you with an FCA-regulated, independently vetted adviser. This is information, not personal advice, and investments can fall as well as rise.
In summary
- Aim for around 10–15% of gross income towards long-term goals, including your pension.
- Secure an emergency fund and clear expensive debt before you start investing.
- Capture any employer pension match first: it is effectively free money.
- Even £50–£100 a month compounds into a meaningful sum over the decades.
- Work backwards from your goal, match each pot to the right account, and automate the payment.
Sources and further reading
- Investing basics MoneyHelper
- Check the Financial Services Register Financial Conduct Authority
- Individual Savings Accounts GOV.UK
Read the full guide
For the complete picture, see our in-depth guide: How to Start Investing: A Beginner’s Guide.
Speak to a vetted investment management specialist
This is free information, not personal advice. When you’re ready, we’ll match you with an independently vetted, FCA-regulated specialist, free, and with no obligation.