This might not surprise you…

But most self-published nonfiction titles sell fewer than 200 copies over their entire lifetime.

At a typical royalty of around £2 per copy on a £4.99 eBook, that’s roughly £400 in total earnings per book.

However, many of those self-published books are utter rubbish – vanity projects, really, which don’t target a pressing need or problem, and therefore don’t have enough demand or perceived value.

If you were instead to publish a decent self-help or business eBook title that DOES tick those boxes, you could be making £80–£300 per month from a single title.

That’s okay… and I’m sure you wouldn’t sniff at that amount coming in as passive income.

But the figures become more interesting when you look at authors who treat publishing as a portfolio business rather than a one-book gamble.

A 2024–25 survey found that the average serious indie author has published 8 books…

And that those earning over £15,000 per month had an average of 61 titles in their backlist, generating multiple revenue streams.

Of course, that’s the extreme end of the market…

But it goes to show that more titles mean more visibility…. more promotional opportunities… and a stronger compounding income over time.

And it gets even better if you think about what a series of successful eBooks could do OUTSIDE your sales earnings.

Because you can also use them to build a list of email subscribers or Substack subscribers… where even more revenue streams can develop.

So if a well-positioned book earns a conservative £100–£250 per month in direct sales PLUS indirect revenue through email marketing, subscription revenues and affiliate sales…

Then a portfolio of just 10+ titles starts to make a £3,000-£5,000 per month income target very achievable.

This is something I call ‘ebook stacking’.

Why Stacking Works

Most people who create and sell eBooks think only about creating one product. And they tend to be disappointed when their income is only a trickle.

A single £7 eBook needs to sell 430 copies a month to hit £3,000.

That’s a tough ask.

However, instead of creating a single eBook and hoping it sells, you could build an interlinked portfolio of eBooks around a single niche or audience.

Each one serves a purpose…

Some attract readers… some convert them into buyers… some upsell them further…. and some funnel them onto your email list where the real long-term income is built.

These don’t all need to be full-length books, they can also be smaller guides and micro-manuals – and you can use AI to help you plan and write them,

Done right, this turns eBooks into a scalable digital product business.

• 5 eBooks at £7–£12 each, averaging 100 sales per month across the range could bring you £3,500–£6,000/month
• An email list of 500+ subscribers means you can then launch your new titles directly to the audience and ALSO potentially sell them other related products to earn an affiliate commission.
• Returning customers (people who loved Book 1 and bought Books 2, 3, and 4) dramatically reduce your cost per acquisition
• Finally, you could generate an income by putting extra ongoing content behind a paywall, for instance on Substack, where people pay you a monthly subscription.

So every new book you add makes the whole portfolio more valuable, not just that one title.

How to Plan a Stacking Business

Begin by targeting a niche. Look for an audience with ongoing problems (health, money, skills, business).

These should be people who already spend money on books, courses and coaching,

Make sure the subject contains enough sub-topics to sustain 6–10+ eBooks without repetition.

Examples include…

• Freelancing for beginners
• Women’s health
• Personal finance for young professionals
• Dog training for new owners.

Put a chosen niche market into an AI tool and ask it if it can come up with 10 distinct eBook titles right now.

If it can do so, then your eBook business is stackable.

For example, you could use this prompt: “I want to create a series of interlinked eBooks targeting an audience, across the next year. Give me 10 distinct book titles for the following niche: freelancing for beginners.”

And AI might give you titles like:

1. The First £1,000: A Beginner’s Guide to Getting Paid as a Freelancer
2. From Zero to Portfolio: Building Credibility When You Have No Experience
3. The Winning Proposal: How Beginners Turn Enquiries into Paying Freelance Clients
4. The £25/Hour Freelancer: Simple Skills You Can Start Selling This Month
5. Clients on Tap: Finding Consistent Freelance Work Without Platforms
6. The 10-Hour Freelancer: Building Income Around a Busy Life
7. Retainer Clients: How to Turn One-Off Jobs into Monthly Income
8. Freelance Systems: How to Organise Your Business Like a Pro (Even as a Beginner)
9. The AI Freelancer: Using ChatGPT & Simple Tools to Work Faster and Earn More
10. From Freelancer to Freedom: When and How to Raise Your Rates, Specialise, or Scale

Map Your Stack Architecture

Before you write a word, map the full portfolio structure.

Each eBook should occupy a distinct role:

• The Entry Point (£5–£9) — Your lowest-barrier product. It solves one specific, immediate problem.
  Think of it as a paid ‘lead magnet’.
• Micro Manuals and Guides (£5–£9) — Worksheets, templates, swipe files and planners. These can also be lead magnets, or companion titles that you sell alongside your regular titles, or as bonuses.
• The Core Stack (£9–£15 each) — 2–4 books that go deeper on the journey. Each one solves the next problem your reader faces. The reader who finished Book 1 is your warmest prospect for Book 2.
• The Premium Offer (£17–£29) — A comprehensive guide, workbook, or bundle of your core stack at a discount. This is where your highest-margin sales happen.

A good tip is to continue the conversation you started with AI in the previous step and ask it to suggest titles that fit into the above structure.

It will then give you ideas like this:

🔹 ENTRY POINT (£5–£9)

The First Freelance Client: How to Get Paid Within 14 Days (Even With No Experience)

Role: Paid lead magnet

Problem it solves: “How do I get my first paying client?”

Promise: A simple 14-day action plan to land your first small paid job.

What it covers:

• Choosing a beginner-friendly service
• Creating a 1-page offer
• Writing a simple pitch message
• Where to send it
• Closing the first £100–£300 job

Don’t worry, none of this is set in stone, you just need to have an idea what the overall marketing plan is going to be.

Writing and Publishing

You don’t need the full stack before launching. Start with 2–3 books and build from there.

• Aim for 8,000–20,000 words per eBook.
• Make sure the introduction or foreword contains a promotional pitch for a website or webpage where you can collect their email address. eg “Download your free companion workbook at [insert your website address]”
• Use a consistent structure: Problem → Why it happens → Framework → Step-by-step → Action plan → What’s next (the bridge to Book 2)
• The “what’s next” section at the end of every book is where you soft-sell the next title

Again, here’s where AI can help.

First, make sure you give it a proper brief, including:

• A description of the target reader, including their goals and problems.
• A description of where this fits in your stack architecture, and what the aim and price point will be.
• A brief biography of you as the author (just the details you are happy to share, and which will connect with the target reader)
• A description of the personality you want to show in the book, including your quirks, strengths and flaws.

Once it has all this background information, ask it to suggest contents and structure for the first title you select.

I then recommend that you go through each section, asking AI to write it, and ensuring you ask it to add in as much stuff as possible that makes it unique to you.

• Personal experiences and anecdotes
• Your opinions, ideas and insights
• Research results, studies and stats that you find
• Real life examples and case studies.

These will help you avoid the result being a generic AI book.

You can publish on Amazon KDP but bear in mind that it doesn’t give you the right to email the customer (however that doesn’t stop you promoting your website or lead magnet in the book itself).

You could also use Gumroad or Shopify where you can sell the book and also collect their email addresses.

Build an Email List

Your email list is the most valuable asset in this business. It’s the difference between £500 per month and £5,000 per month.

Think of it as a sales funnel…

1. Reader buys your Entry Point eBook
2. Inside the book, they’re offered a free companion resource – a checklist, template, or mini-guide
3. They visit your landing page and exchange their email for the freebie (lead magnet)
4. They enter your welcome sequence (5–7 emails delivering value and introducing your stack)
5. You email your list weekly – tips, stories, recommendations – and periodically promote your books

Now you have a recurring income asset that grows the more books you sell.

With just 500 subscribers you could be making an extra £300–£600 per month from promotions of your own books or products you sell on an affiliate basis.

With 2,000 subscribers you’re taking £1,200–£2,500 per month.

The key is to send valuable information AT LEAST once a week, but ideally more.

Finding Customers

Pick 1–2 channels to focus on, including…

• Pinterest (excellent for how-to niches, long shelf life)
• Medium or Substack (write articles, link to books),
• YouTube (positions you as an expert)
• An SEO-optimised blog.

For faster results, you could try Facebook and Instagram Ads. but I recommend you promote a free ‘lead magnet’ rather than the book directly.

If you sell on Amazon, you can also try something known as ‘promo stacking’.

It’s a method used by savvy self-published authors to increase sales momentum by layering multiple promotions together in a sequence.

This is because a single promo rarely moves sales enough to trigger Amazon’s algorithm.

But if you stack several together over 5–7 days, you can push a book up the category rankings and trigger “also bought” associations.

So I hope you can see the potential here…

It’s not easy to turn one or two eBooks into a significant income, but things become very different when you use a stacking strategy like this one.

If you have any questions about this, then fire away!