We have some exciting news to share! The Motley Fool UK has now become The Twelfth Magpie -- an independent, UK-owned company, led by our long-serving UK management team — Mark Rogers, Chris Nials and Heather Adlington. In practical terms, it’s the same team you know, now fully focused on serving our UK readers and members.

Just as importantly, our approach remains unchanged: long-term, jargon-free, and on your side. This site is our new home, and there will be extra tweaks made across the coming few days as we settle in. So if anything looks a little off, please bear with us!

The content of this article was relevant at the time of publishing. Circumstances change continuously and caution should therefore be exercised when relying upon any content contained within this article.

3 costly passive income mistakes to avoid

Passive income can be a minefield. Our writer identifies three common mistakes he seeks to avoid in his portfolio.

You’re reading a free article with opinions that may differ from The Twelfth Magpie’s Premium Investing Services. Become a member today to get instant access to our top analyst recommendations, in-depth research, investing resources, and more. Learn more, and get a free 'Best Buy Now' stock!.

Passive income can be appealing. Investing in dividend shares is one of the favourite passive income ideas of a number of people, including myself. But while investing in dividend shares has appeal, it can also involve risks.

I think being aware of some of the risks can help me avoid them and hopefully increase my potential income. Here are three common mistakes I’d seek to avoid.

Should you buy Rolls Royce shares today?

Before you decide, please take a moment to review this report first. Despite ongoing uncertainties from US tariffs to global conflicts, Mark Rogers and his team believe many UK shares still trade at substantial discounts, offering savvy investors plenty of potential opportunities to learn about.

That’s why this could be an ideal time to secure this valuable research – Mark’s analysts have scoured the markets to reveal 5 of his favourite long-term ‘Buys’. Please, don’t make any big decisions before seeing them.

Mistake 1: over-emphasising historical dividend data

How can one tell what the dividend yield of a given share may be?

The most common method is to look at the most recent dividend, as a percentage of the current share price. That makes sense as it’s the most up-to-date information available. But it’s backward-looking. If I am considering buying a share I am interested in what it might pay me in future, not what it paid out in the past.

I do think historical dividend data can help me in some ways. It helps to show how a company feels about the importance of dividends, for one thing. For example, last year when the outlook was uncertain, Legal & General maintained its dividend while rivals such as Aviva suspended theirs. That can be helpful in managing my own expectations about a company’s willingness to axe its dividend.

The dividend history can also give me some insight on what the dividend will be like if it is maintained at a similar level to before.

But while such information can be informative, it doesn’t give me clear guidance on what the company’s future dividends will be. For that I need to make some judgments of my own based on the available information. For example, I can look at a company’s accounts and see how much free cash flow it has been generating. I can then consider whether I expect it to be able to maintain its free cash flow generation at that level in years to come. To do that I’d consider a variety of questions. Is customer demand likely to grow or shrink? Does the company have pricing power to enable it to maintain its profit margins? Will it need to increase its capital expenditure in coming years, perhaps because it needs to modernise its factories or invest heavily in some new technology?

So while I do pay attention to historical dividend data, I don’t think it’s the most important thing to look at when deciding whether to add a share to my portfolio for its passive income potential. Instead, the key aspect of my analysis is what the dividend might look like in future.

Mistake 2: buying an attractive dividend at an unattractive price

Which of these two dividends sounds more attractive? £2.08 a year or £1.54 a year?

If you’ve answered that question already, you may have done so too fast. A dividend amount in isolation doesn’t help me know whether a share might be a lucrative passive income pick for my holdings. Instead, what I need to know is a share’s dividend yield. That is a function of the dividend but also of the price at which I buy the share. So, for example, if I buy a share at £20, an annual dividend of £2.08 would mean that I got a yield of 10.4%. But if the same share moved up to £35, and I bought it at that price, my dividend yield would only be 5.9%.

This matters a lot for passive income. The price at which I buy the shares today will affect the yield I get for as long as I hold them. If I have £1,000 in dividend shares and the average yield is 3%, I would get £30 of passive income in a year. But if I put the same £1,000 into the same shares at a different price, my passive income might look very different. If I bought the shares when they were 50% cheaper, my passive income would be £60. If I purchased them when they were 50% more expensive, my passive income would be £20.

Such swings in price over the course of several years aren’t exceptional. Consider as an example the popular dividend share BP. This year alone it has traded as low as £2.51 but also as high as £5.08, more than double its low. Buying at the lower price, I would now be getting slightly over double the yield I would have received if I bought at the higher price.

So I think it’s a mistake to look just at the absolute size of a dividend when I am hunting for passive income ideas. Instead, I also need to consider the share price at my time of purchase.

Mistake 3: ignoring share price falls

Another mistake I try to avoid when looking at passive income ideas for my portfolio is neglecting the threat of long-term share price decline. Let’s say a share offers me a high yield, but meanwhile its share price declines markedly over the course of years. Am I just receiving with one hand what is being taken away with the other?

The answer to that depends on the exact circumstances. If I continue to hold the shares and the share price decline is just because a company has fallen out of favour with investors, it might not matter for me. I could still receive my passive income — and the share price may have recovered by the time I come to sell the shares years down the line.

But it is a different situation if the share price decline reflects a worsening business. That could mean that I am unable to recoup my original investment if I decide to sell the shares in future. On top of that, the worsening business could mean dividends are cut at some stage. Even with an attractive initial yield, if the share price falls far enough, I may still lose money over time.

So when choosing passive income shares for my portfolio, I try to assess whether the share price looks overvalued. If it does, I would be wary of buying the shares no matter how high the yield might be.

Christopher Ruane has no position in any of the shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

More on Investing Articles

Rolls-Royce's Pearl 10X engine series
Investing Articles

Is the best still to come for Rolls-Royce shares?

Christopher Ruane explains why he thinks Rolls-Royce shares could yet push even higher from here -- and whether he's ready…

Read more »

Finger clicking a button marked 'Buy' on a keyboard
Investing Articles

Is this soaring penny share set for an explosive 2026?

This penny share company has suffered because its business has been through a tough time. But so far this year,…

Read more »

Young mixed-race woman jumping for joy in a park with confetti falling around her
Investing Articles

Up over 100%, are these FTSE 100 names still among the top stocks to buy?

As they have more than doubled over the past year, Andrew Mackie asks whether these two FTSE 100 stocks are…

Read more »

Stack of one pound coins falling over
Investing Articles

Here’s how saving £3 a day could lead to an £11,925 yearly passive income

Can saving small amounts regularly lead to a big passive income? Our author explores one investing strategy that might do…

Read more »

Black woman using smartphone at home, watching stock charts.
Investing Articles

3 crazy Nasdaq growth stocks I’m avoiding like the plague in June

This trio of Nasdaq shares offers eye-popping growth potential across space and artificial intelligence. What's not to like?

Read more »

Investing Articles

Is this former stock market hero now the ultimate FTSE 100 buy and hold?

This UK blue chip was the darling of the stock market for years, but lately it's struggled and investors have…

Read more »

Diverse group of friends cheering sport at bar together
Investing Articles

3 shares to consider buying for the 2026 World Cup

The 2026 World Cup could throw up some lucrative opportunities for investors. Here are three shares to consider buying for…

Read more »

The Milky Way at night, over Porthgwarra beach in Cornwall
Investing Articles

Is the SpaceX IPO the best growth stock opportunity in a generation?

How about a mix of space exploration, satellite communications, and artificial intelligence? That's what SpaceX stock is all about.

Read more »