The UK stock market’s full of high-yielding dividend shares but, unsurprisingly, it’s the biggest companies that get the most attention. However, a number of Alternative Investment Market (AIM) stocks are offering some incredible yields at the moment.
In fact, according to the league tables, of those with a market-cap of at least £50m, the two highest are suggesting a return of at least 16.6%. But how sustainable are they? Is it a case of being too good to be true? Let’s find out.
1. Going green
At 17.8%, the highest-yielding of our duo is Impax Asset Management Group (LSE:IPX). But it’s a perfect demonstration of why such astonishing yields need to be investigated further. That’s because the figure quoted is based on amounts paid over the past 12 months, a period that’s seen its share price fall by 30%.
The group’s been experiencing a long-term decline in assets under management (AUM). During the year ended 30 September 2025 (FY25), AUM fell by £11.1bn. And compared to FY24, revenue was 16.6% lower and adjusted operating profit fell 36.2%.
As a result, the company’s cut its dividend. Having kept it unchanged at 27.6p for FY22-FY24, it’s decided to return 12p to shareholders for FY25. This means the quoted yield is misleading. In fact, the forward yield is currently (6 February) 7.9%. Still impressive, but a long way short of the headline number.
Despite its troubles, the company remains debt free. And its directors are “highly confident” about the group’s long-term prospects. Its boss recently said: “The economic case for the transition to a more sustainable economy continues to build, as consumers increasingly prefer more efficient, less polluting goods and services“.
But even with a potential return of 7.9%, the stock’s too risky for me. Until I see a sustained inflow of AUM, I’m going to look elsewhere.
2. Mind your language
Next, with a trailing 12-month yield of 16.6%, we have RWS (LSE:RWS). Again, its share price has tanked over the past 12 months. Since February 2025, it’s fallen 45%.
Although the content and language solutions group uses artificial intelligence (AI) as part of its product offer, there are concerns that the technology could disrupt its business model. The group’s boss acknowledges this: “The pace of change in our industry, fuelled by the global content explosion and rapid technology evolution, demands that RWS adapts quickly to succeed”.
During the 12 months to 30 September 2025, pre-tax profit fell 43% year-on-year. As a consequence, it cut its full-year dividend by 43%. It’s a pity because since the pandemic, it’s made good progress in increasing its payout. The forward yield is a more modest — but still impressive — 9.4%.
However, once more, there’s too much uncertainty surrounding the group for me to want to invest.
The final word
The lesson from all this is that high-yielding shares should be treated with extreme caution. It’s important to look behind the figures quoted.
But that doesn’t mean we should throw the baby out with the bath water. There are plenty of good dividend payers on AIM. Okay, their yields are more modest than those quoted here but the payouts are more likely to be sustained. And a number of these smaller stocks have an excellent track record of steadily increasing their dividends.
