“The smaller, the better,” says the London Business School, which has examined the performance of smaller companies since 1955. The compound annual return of the Numis Smaller Companies index, representing the bottom 10% of the UK market, has been 14.7% since then, 3.4% ahead of the All-Share index. The yearly return of the Numis 1000, representing the bottom 2%, has been 16.3%.
Excluding investment companies, there are over 100 listed “micro-cap” companies with market values below £100m, but they only account for 0.2% of the total market by value. Another 50 have market values of £100m-£200m, adding 0.4% of total market value, but the inclusion of listings on Aim, the junior market of the London Stock Exchange, trebles the number of stocks.
Scouring this mass of tiddlers for bargains are two trusts, the River & Mercantile UK Micro Cap Investment Company (LSE: RMMC), launched in late 2014, and the Miton UK MicroCap Trust (LSE: MINI), launched a few months later. Both have assets of a little over £100m; target firms with a market value below £150m; and trade on discounts to net asset value (NAV) of around 3%. However, George Ensor, manager of RMMC, points out that his trust has also returned capital to investors four times, £57m in total, in order to limit its size. It has just 41 holdings and without that limit would have to increase that number or have larger and less liquid holdings. Gervaise Williams, MINI’s manager, is happy with 128 holdings.
MoneyWeek
Subscribe to MoneyWeek today and get your first six magazine issues absolutely FREE
Sign up to Money Morning
Don't miss the latest investment and personal finances news, market analysis, plus money-saving tips with our free twice-daily newsletter
Don't miss the latest investment and personal finances news, market analysis, plus money-saving tips with our free twice-daily newsletter
The tortoise and the hare
It’s been a story of the tortoise and the hare. RMMC raced away under its first manager, who was then forced to leave owing to an obscure compliance issue. Its investment return has been 143% over five years and 44% over one. MINI has returned 94% over five years, but 92% over one. Both trusts struggled in 2018-2019, but MINI, with a strong bias towards value, struggled more. Having withstood the sell-off in early 2020 better than RMMC, it has since soared. This is probably due to Williams’s focus on “highly cash-generative stocks”.
Choosing between them is tough. Ensor is clearly finding his feet, but lacks Williams’s 30 years of experience. Inevitably, both trusts are full of stocks few people will ever have heard of. Ensor has moderated the growth focus of his predecessor: “growth is important, but we don’t want to overpay for it”. Williams notes that “it’s important not to get carried away by a good story”, though his exposure to information technology companies is, at 14%, ten percentage points higher than Ensor’s. By contrast, Ensor’s exposure to the consumer and healthcare sectors is 32% compared with 17% for Williams.
Unparalleled choice in the UK
Williams sees particular opportunity in “the cyclicality of various financial and commodity micro caps, providing greater upside at a time of recovery from the pandemic. The potential could be even greater if [inflation takes off]. They have been out of favour for so long that it is easy to underestimate the full scale of their upside”. He has pushed exposure to these sectors up to about 40% of the portfolio compared with 32% for RMMC.
Neither trust has any borrowings and both have plenty of cash. As to the outlook, “what remains curious is how easy it is to find attractively valued companies capable of compounding value for shareholders over a multiyear horizon,” says Ensor. “The UK stockmarket is possibly unparalleled from this perspective.” Williams thinks that the low valuations of micro caps provide “better potential for recovery than other areas of the market” and thinks they could be “at the start of a brand-new supercycle”. This corner of the UK market is easily ignored, but promises rich returns for investors in either trust.
Get the latest financial news, insights and expert analysis from our award-winning MoneyWeek team, to help you understand what really matters when it comes to your finances.

Max has an Economics degree from the University of Cambridge and is a chartered accountant. He worked at Investec Asset Management for 12 years, managing multi-asset funds investing in internally and externally managed funds, including investment trusts. This included a fund of investment trusts which grew to £120m+. Max has managed ten investment trusts (winning many awards) and sat on the boards of three trusts – two directorships are still active.
After 39 years in financial services, including 30 as a professional fund manager, Max took semi-retirement in 2017. Max has been a MoneyWeek columnist since 2016 writing about investment funds and more generally on markets online, plus occasional opinion pieces. He also writes for the Investment Trust Handbook each year and has contributed to The Daily Telegraph and other publications. See here for details of current investments held by Max.
-
The most influential people of 2025Here are the most influential people of 2025, from New York's mayor-elect Zohran Mamdani to Japan’s Iron Lady Sanae Takaichi
-
Millions of parents are missing out on up to £720 a year in extra pension cash – are you affected?A mum who narrowly missed out on the pension boost said she “never knew the government rule existed” and wants other parents to use it
-
8 of the best properties for sale with indoor gymsThe best properties for sale with indoor gyms – from a four-storey mews house in London’s Knightsbridge, to a 1920s Arts & Crafts house in Melbury Abbas, Dorset
-
Top stock ideas for 2026 that offer solidity and growthLast year’s stock ideas from MoneyWeek’s columnist and trader, Michael Taylor, produced another strong performance. This year’s stocks look promising too
-
Market predictions for 2026: Will Dubai introduce an income tax?Opinion My 2026 predictions, from a supermarket merger to Dubai introducing an income tax and Britain’s journey back to the 1970s
-
Stock markets have a mountain to climb: opt for resilience, growth and valueOpinion Julian Wheeler, partner and US equity specialist, Shard Capital, highlights three US stocks where he would put his money
-
The steady rise of stablecoinsInnovations in cryptocurrency have created stablecoins, a new form of money. Trump is an enthusiastic supporter, but its benefits are not yet clear
-
SRT Marine Systems: A leader in marine technologySRT Marine Systems is thriving and has a bulging order book, says Dr Michael Tubbs
-
Goodwin: A superlative British manufacturer to buy nowVeteran engineering group Goodwin has created a new profit engine. But following its tremendous run, can investors still afford the shares?
-
A change in leadership: Is US stock market exceptionalism over?US stocks trailed the rest of the world in 2025. Is this a sign that a long-overdue shift is underway?