Duplication vs. Cost Caps vs. the 20% Increase: The Only Meta Scaling Method We Still Trust

A founder messaged me last week with one line: "We're finally profitable at $2k a day, how do I push it to $10k without breaking everything?"

It's the most common question I get, and it almost never comes with a creative problem attached. The ads are working. The unit economics make sense. They just don't know which lever to pull, because every YouTube video and every Slack group gives them a different answer.

So here's my take, ranked, after years of doing this for Shopify brands across a fair few accounts. There are really only three Facebook ads scaling methods most people argue about: duplication, cost caps, and the boring 20% budget increase. I trust exactly one of them as a default. I'll walk you through all three and tell you why the other two keep ending in tears.

The three methods, in plain English

Before I rank them, let's make sure we mean the same thing.

Duplication is where you take a profitable campaign and copy it, usually at a much bigger budget. Profitable at $100 a day? Duplicate it at $500 or $1,000 and let the copies run. The idea is you scale spend fast by stacking winners on top of winners.

Cost caps (and bid caps, which behave similarly) are where you set a large budget and tell Meta a maximum cost per result. Say $25 per purchase. Meta then only spends when it can find buyers at or under that number. In theory you only spend when you make money.

The 20% increase is the dullest of the lot. You run an Evergreen CBO campaign, look at the last 3 to 7 days, and nudge the budget up 20% on good stretches or down 20% on bad ones. Once a day. That's the whole method.

Now, here's my ranking, worst to best.

Third place: cost caps, the strategy that looks like free money

On paper, cost caps are the dream. You name your price, Meta respects it, you never overpay. I understand exactly why founders fall for them. "Only spend when you're profitable" is a sentence that sells itself.

In reality, I've watched cost caps cause more quiet damage than any other method on this list.

The first problem is the one nobody warns you about: Meta breaks. Not often, but it happens, and it happens at the worst time. A skincare brand we did a Signal/Noise Audit for had a cost cap campaign sitting at a $30 target. One weekend the system glitched, ignored the cap entirely, and spent close to $9k in a day at a cost per purchase north of $80. No alert. No safety net. They found it on the Monday. That was roughly a fortnight of margin gone because they'd trusted a setting to hold a line it isn't actually contractually obliged to hold.

The second problem is slower and sneakier. Cost caps strangle your data. When you're trying to learn which creatives work, you need Meta to actually spend on them. A tight cap tells the algorithm to only chase the cheapest, most obvious conversions, so half your new creatives never earn enough spend to tell you anything. You sit there with ten ads and real signal on two of them.

And there's a third one I rarely see discussed. Some of your best creatives have an ugly cost per result on their own, but they pull a load of new people into the funnel that your other ads then convert. A cap looks at that single "expensive" ad in isolation, decides it's a loser, and chokes it. You've just killed the thing that was feeding your whole funnel.

Here's the thing. I've pulled a lot of accounts off cost caps, and almost every time the story is the same. CPA looked stable and tidy. Growth was flat for months. The moment we moved them onto open budgets and fed the algorithm properly, we could see how restrictive the cap had been all along. Cost caps can suit a mature, narrow account that just wants to defend a CPA. For a brand that's actually trying to grow, I think they're a quiet handbrake.

Second place: duplication, the strategy that scales fast right up until it doesn't

Duplication is more honest than cost caps, at least. It does what it says. If you genuinely need to get from $1k a day to $5k a day this week because stock is moving and the window is now, duplication can get you there faster than anything.

I just don't trust it as a default, and I've got scars to explain why.

The core problem is that a campaign being profitable at $100 a day tells you almost nothing about whether it survives at $1,000 a day. When you 5x or 10x the budget overnight, you're asking Meta to find ten times as many buyers, right now, for the same ad. Sometimes it holds. Often it doesn't, and the ad that printed money at $100 starts bleeding at $1,000 because the algorithm is reaching well past the people who were actually keen.

Then there's auction overlap. Stack four copies of the same campaign and they start bidding against each other in the same auctions. You're now paying more to compete with yourself, which is about as silly as it sounds.

Let me give you the version I've seen play out more than once. A homewares brand sitting at a comfortable ~$25k a month decided to go big. They duplicated their main campaign three times and roughly doubled blended spend overnight. For about 48 hours it looked glorious. Then performance fell off a cliff. CPA didn't just creep, it nearly tripled, the account went into that horrible up-down-up-down spiral, and they panicked and tore the duplicates back down. Trouble is, by then they'd dumped so much erratic spend in that the learning was scrambled, and even the original campaign that had been humming along never quite recovered its old numbers. It took the better part of a month to claw back to where they'd started. They didn't scale. They went backwards and paid for the privilege.

That's the real cost of duplication done carelessly. It's not just that the new spend might not work. It's that a bad duplication run can poison the campaign that was already working, and you spend weeks rebuilding instead of growing. When I do see duplication used well, it's slow, deliberate, one copy at a time with a clear kill rule, by someone watching the account daily. That's a long way from the "double it and pray" version most founders try first.

First place: the 20% increase, the boring method that actually compounds

So we land on the one I'd hand a brand new account to without thinking twice. It's the least exciting, the easiest to manage, and the hardest to argue with once you sit down and do the maths.

The method is almost insultingly simple. Look at the last 3 to 7 days of your Evergreen CBO. If the numbers are healthy, push the budget up 20%. If they're soft, pull it down 20%. Once a day, that's it. No new campaigns to babysit, no cost cap to second-guess, no overnight cliff edges.

The objection is always the same, and it's fair: "20% sounds way too slow." A 20% bump on $1,000 a day is only $200. Feels like nothing.

Here's where it gets interesting. To put this into perspective, run the compounding out. Start at $100 a day and increase 20% daily and you cross $1,000 a day in roughly two weeks. Keep going and by day 30 you're theoretically over $20,000 a day. Now nobody scales in a perfectly straight line, you'll have down days and plateaus, so treat that as the shape of the thing rather than a promise. But the shape is the whole point. Steady percentage growth bends upward fast precisely because each increase is bigger than the last. You're scaling off a number that keeps getting larger.

There's a reason I keep coming back to "slow is fast." Picture the homewares brand from earlier, except they'd never touched duplication. Same starting point, ~$25k a month, healthy ROAS. They just nudge the budget up 20% on the good stretches and ease off on the rough ones. No cliff, no scramble, no month spent recovering. Three or four months of that compounding quietly and they're in genuinely different territory, having never once risked the account in a single day. That's the bet. Small, survivable steps that stack, versus big swings that occasionally pay off and occasionally set you back a month.

The other thing I love about 20% is how easy it is to react to. Going from $10k to $12k a day is a jump I can read in a couple of days. If it holds, great, I go again. If it wobbles, I drop straight back to $10k and I've barely risked anything. Compare that to discovering on a Monday that a cost cap quietly torched $9k, or that a duplication run knackered your best campaign. The 20% method almost never hands you a disaster, because it never lets you make a disaster-sized move.

I do want to be straight about the one real catch. The 20% method only works if the fundamentals underneath it are sound. Strong creative, a product people genuinely want, a landing page that converts. If those aren't in place, no scaling method on earth saves you, you're just pouring more money into a leaky bucket faster or slower. Budget scaling is the amplifier, not the engine. Get the engine right first.

Where I'd land if it were your account

If you're trying to choose a default Facebook ads scaling method, I think it's genuinely not close. Cost caps quietly cap your growth and occasionally break in your face. Duplication scales fast and then, often enough, undoes a month of progress in a weekend. The 20% increase is dull, survivable, and it compounds, which is exactly what you want when you're building a brand meant to last years rather than flipping a product for a quick win.

So before you reach for the dramatic lever, I'd ask one honest question: are your ads actually failing, or do you just not trust how unexciting steady scaling feels?

If it's the second one, you probably already have your answer. And if you genuinely can't tell whether the account is ready to scale at all, that's exactly what a Signal/Noise Audit is for. A second set of eyes on the structure, the creative, and the unit economics will tell you whether you're sitting on a 20%-a-day machine, or a leaky bucket wearing a nice ROAS.

What's holding your account back right now - the scaling method, or the thing underneath it?