Last reviewed by Robert Prime — May 2026
Introduction
Amazon Ads is the highest-leverage marketing lever for indie authors on KDP. Most authors get to £10-£20/day spend reliably. Scaling beyond — to £50/day, £100/day, £300/day — is where most authors stall.
The reason isn't budget. The reason is that the tactics that work at £10/day don't work at £100/day. Scaling requires structural changes to your campaign architecture, keyword strategy, and bid management.
This guide covers what actually changes when you scale, the prerequisites, the trap that catches most authors, and a realistic 90-day plan from £10/day to £100/day.
Prerequisite: the book has to convert
If your book's Amazon detail page converts at under 5% of click traffic, scaling ads will just amplify the leak. You'll spend £100/day to discover the listing isn't converting.
Before scaling spend, the book needs:
- Cover that performs at thumbnail size. Test with the free 60-second audit.
- At least 25 reviews (4.0+ average).
- Compelling book description — first 200 characters must hook (above the "Read more" fold). See book description writing.
- Priced competitively for the genre.
- A look-inside that delivers on the cover/blurb promise.
A book that converts at 8%+ can sustain higher ad spend profitably. A book at 2% cannot — fix the listing first.
Why £10/day tactics don't scale
At £10/day, you can run 3-5 broad campaigns and they'll spend evenly. At £100/day, those same 3-5 campaigns either:
- Spend it all on the cheapest highest-volume keywords (often the worst converters)
- Run out of impressions and stop spending
You need more campaigns, more granular targeting, and per-keyword bid discipline.
The scaling-ready campaign architecture
A book scaled to £100/day typically runs 20-30 active campaigns segmented as:
By ad type (3 layers):
- Sponsored Products — Auto (Amazon picks keywords) — discovery layer
- Sponsored Products — Manual (you pick keywords) — control layer
- Sponsored Brands (brand banner ads, requires registered brand) — awareness layer
By keyword intent:
- Branded keywords — your author name, book title, series name. Low CPC, high conversion. Always profitable.
- Competitor author keywords — readers searching for similar authors. Moderate CPC, moderate conversion.
- Genre keywords — readers searching for the genre. Higher CPC, lower conversion. Volume.
- Long-tail keywords — specific themes, settings, plot elements. Low volume, very high conversion.
By match type:
- Exact — only matches the exact keyword. Highest control, highest CPC.
- Phrase — matches phrases containing the keyword. Discovery + control.
- Broad — Amazon's match algorithm. Discovery layer.
Keyword research for scale
At low spend, you find keywords with Amazon's auto-suggest. At high spend, you need a system:
- Mine your auto campaigns. Auto campaigns generate search-term reports — keywords Amazon found that converted. Harvest these into manual exact-match campaigns.
- Mine competitor listings. Look at the "frequently bought together", "customers also bought", and category pages. Note author names, book titles, series names. These become competitor-author keywords.
- Mine reader reviews. Reviews use specific language readers care about. "page-turner", "couldn't put it down", "slow-burn romance" — these are keywords.
- Use third-party tools. Publisher Rocket (one-off £99) and KDSpy (£35-£60/month) accelerate keyword research significantly.
A scaled campaign architecture has 200-500 active keywords, not 20.
ACoS targets through the book lifecycle
ACoS (Advertising Cost of Sales) = ad spend / sales revenue from those ads. Lower = more profitable.
The right ACoS target depends on lifecycle:
| Stage | Target ACoS | Strategy |
|---|---|---|
| Launch (first 90 days) | 50-100%+ | Aggressive — buying reviews and rank, not profit |
| Establishment (90-180 days) | 30-50% | Balancing growth and profit |
| Mature (180+ days) | 15-30% | Profitable spend only |
| Long-tail (1 year+) | <20% | Maintenance |
A common scaling mistake: targeting 30% ACoS during launch. You'll under-spend and miss the launch window.
The launch-vs-evergreen mix
For a series author, ad spend should split:
- 70% on the current launch book during its first 90 days
- 30% on backlist evergreen maintaining series visibility
Once the launch book matures, rebalance:
- 40% on backlist (now including the once-launched book)
- 40% on new launch
- 20% on series box sets and audiobook
Bid management at scale
At £10/day, you can manually adjust bids weekly. At £100/day across 20 campaigns, manual management breaks down.
Three options:
- Manual with discipline — weekly review of top spenders, adjust bids by 10-20% based on ACoS. Time cost: 2-3 hours/week.
- Amazon's dynamic bidding — Amazon adjusts your bid based on conversion likelihood. Set "down only" for safety, "up and down" for aggression. Less control but less time.
- Third-party tools — Ad Badger, PPC Entourage, Helium 10 Adtomic — automate bid adjustments. Cost: £40-£200/month. Worth it once you're spending £2,000+/month on ads.
The trap: spending without scaling
The single biggest mistake at the £30-£50/day transition: you increase budgets without changing structure.
Symptoms:
- Your campaigns spend their full budget but ACoS climbs
- New keywords keep underperforming
- One or two keywords absorb most of the budget (and lose money)
- Sales velocity doesn't increase proportionally to spend
The fix is always structural — add more campaigns, segment by intent, separate launch from evergreen, harvest auto-campaign search terms into manual exact-match.
If you increase from £10 to £30 by just raising budgets on existing campaigns, you'll usually burn money. Add new specialised campaigns instead.
A 90-day scaling plan
Month 1 — foundation:
- Audit current campaigns; pause anything with 60%+ ACoS for 60 days
- Run a Sponsored Products Auto campaign with £15/day for 30 days for keyword discovery
- Set up a branded keywords campaign (author name + book title)
- Daily spend: rises from £10 to £25
Month 2 — segmentation:
- Harvest top converting keywords from the Auto campaign into 3-5 manual exact-match campaigns segmented by intent (branded, competitor, genre)
- Add 5 Sponsored Brands campaigns (if brand-registered)
- Start a Sponsored Products Manual campaign with phrase-match on top genre keywords
- Daily spend: rises from £25 to £55
Month 3 — optimisation:
- Add competitor-author manual campaigns (5-8 campaigns each targeting one competitor)
- Add long-tail keyword campaigns (theme/setting/plot-element)
- Layer Sponsored Brands video ads
- Daily spend: stabilises at £80-£100, ACoS at 25-35%
By the end of 90 days you should have 20-30 active campaigns, several hundred active keywords, and a stable spend at the new level.
UK considerations
- Amazon.co.uk has lower ad competition than Amazon.com in most categories. Bids are 30-50% lower on the UK platform.
- UK ads spend a higher proportion on Sponsored Products because Sponsored Brands eligibility (brand registry) requires a registered trademark — many UK indie authors haven't registered yet.
- Track UK and US separately. Same book, different markets, different ACoS. Don't pool them.
- VAT on Amazon Ad spend — Amazon Ads invoices include VAT, deductible against your self-employed income.
What about Facebook and BookBub ads?
Amazon Ads is the highest-leverage lever for most indie authors because the traffic is at the point of purchase. Facebook and BookBub are secondary.
BookBub Featured Deal — when you can get one (acceptance rate ~10%), it's the single most valuable promo in indie publishing. £400-£900 cost, often £3,000-£10,000 sales return on a single day. Worth applying for every 90 days.
BookBub Ads (CPC platform) — separate from Featured Deals. Lower volume than Amazon Ads, useful for international targeting.
Facebook Ads — high time investment, harder ROI tracking. Useful for building email list, less useful for direct book sales.
For the £10 → £100/day journey: focus on Amazon Ads. Add the others once Amazon spend is dialled in.
Common mistakes
- Scaling without listing fix. Cover/blurb/reviews need work first.
- One big campaign. Splits attention. Always segment.
- Same bid across all keywords. Branded should bid much lower than competitor; long-tail much higher than broad genre.
- Ignoring search-term reports. This is where most authors miss the highest-converting keywords.
- Setting and forgetting. Amazon Ads requires weekly review at scale.
- Targeting US ACoS targets for the UK. UK conversion patterns differ; recalibrate per market.
The bottom line
Scaling Amazon Ads from £10/day to £100/day is structural, not budgetary. Add more campaigns, segment by intent, harvest auto-campaign keywords into manual exact-match, and run different ACoS targets per book lifecycle stage.
Prerequisite: the book must convert at 5%+. Below that, ads amplify the leak. Fix listing first.
Most authors at the £10-£30/day plateau are running too few campaigns with too few keywords and too little segmentation. The fix is more campaigns and more keywords, not more budget on the existing ones.
Frequently asked questions
Can I scale to £100/day on a single book?
For a strong-converting book in a high-volume genre (romance, thriller, mystery), yes. For literary fiction or niche non-fiction, the ceiling is usually lower.
Should I run ads in KDP Select / KU?
Yes. KU page-reads count toward ad attribution and are a meaningful revenue stream. Treat them as part of the return.
What's a "good" ACoS for evergreen?
15-30% for an established book in a competitive genre. Below 15% usually means you're under-spending.
Should I use Amazon's algorithmic recommendations?
Amazon's "Suggested bids" are conservative. "Up and down" dynamic bidding can work for established profitable keywords but burns money on unproven ones. Default to "down only" + manual bids until you have data.
How long until I see results from a campaign?
14-30 days for meaningful data. Don't pause a campaign before 14 days unless ACoS is over 100%.
What if my book is in KDP Select — do ads compete with the free promo period?
No. You can run ads during free promo periods; the ads drive impressions and the free promo drives downloads. Many authors stack ads + free promo at launch.
