Facebook Ads in London? Ditch "Best Time" Thinking

I see this question a lot, and I'm going to be brutally honest with you: you’re asking the wrong question. Trying to find the "best time to run Facebook ads" is a bit like trying to find the best time to breathe. For a business that needs to make sales, the answer should be 'all the time'. It's a relic from a time when ad platforms were much dumber.

The old logic was that you'd schedule your ads to show up when you assumed people were browsing – lunch breaks, evenings, weekends. You’d turn them off overnight to "save money". Today, doing that is one of the fastest ways to kneecap your campaign performance, especially in a 24/7 city like London.

Meta's advertising algorithm is now an incredibly sophisticated machine learning system. Its entire job is to take your budget and find the specific people within your target audience who are most likely to take the action you want (like making a purchase), at the exact moment they are most likely to do it. When you impose a rigid schedule, you're tying one hand behind its back. You're telling the algorithm "Don't show my ad to the night-shift worker browsing on their break at 3am, or the new mum scrolling during a late-night feeding," even though that might be the perfect, distraction-free moment for them to buy. You restrict its ability to learn and optimise, which almost always leads to a higher cost per purchase and more unstable results.

So, if timing isn't the magic bullet, what is? For a London-based e-commerce store, success hinges on three things that matter far more: mastering your audience, crafting an irresistible offer, and understanding real seasonality. Let's get into what actually works.

Who Exactly Are You Selling To in London?

London isn't one single market; it's a patchwork of dozens of distinct tribes and communities. Simply targeting "People who live in London" is lazy and expensive. You're lumping a banker in Canary Wharf in with a creative in Peckham and a student in Mile End. Their incomes, interests, and buying habits are worlds apart. You have to go deeper.

Your Ideal Customer Profile (ICP) isn't a demographic; it's a pain point. Forget "Females, 25-40, living in London." Instead, think about the problem you solve. Are you selling sustainable, locally made clothing? Your ICP might be a time-poor but ethically conscious professional in Islington who's frustrated with fast fashion's waste. She listens to podcasts like 'How to Fail with Elizabeth Day', reads The Guardian, and follows brands like Patagonia and Finisterre. See how much more specific that is? Now you have interests you can actually target.

Here's how to think about layering your London targeting, from broad to hyper-specific:

• -> Postcode Targeting: Don't just target the whole city. If you're selling high-end homeware, you could test targeting postcodes like SW3 (Chelsea) or W8 (Kensington). Selling vintage streetwear? Try E8 (Dalston) or SE15 (Peckham). This immediately refines your audience.
• -> Interest & Behaviour Layering: This is where the real magic happens. Combine those location targets with interests that reflect your ICP's lifestyle. Let's take that sustainable clothing example. You could target women in Islington (N1) who are also interested in 'Sustainable fashion', 'Organic food', and 'Farmers' markets'. Or you could target people who have recently engaged with the 'Shop Small' button on Instagram.
• -> Lookalike Audiences: Once you have some sales data (even 100-200 purchases is a start), this becomes your most powerful tool. Create a Lookalike Audience based on your customer list. Meta's algorithm will analyse the thousands of data points associated with your existing buyers and go find more people across London who look just like them. This almost always outperforms interest-based targeting.

Your goal is to build a structured funnel that guides potential customers from initial awareness to a final purchase. A disorganised approach to audiences is a recipe for wasted spend.

When Timing Actually Matters: UK Retail Seasonality

So if daily scheduling is a fool's errand, does that mean timing is completly irrelevant? No. You just need to zoom out. Instead of thinking in hours and days, you need to think in seasons and holidays. This macro-timing is where you can find a massive competitive edge.

The UK retail calendar has a distinct rhythm, and your ad campaigns should dance to it. Your budget, creative, and offers should flex throughout the year to capture demand when it peaks. Forgetting to plan for Black Friday in London is like a pub forgetting to order extra beer for a football final – you're just leaving money on the table. A campaign that works in the quiet of February will get obliterated in the competitive frenzy of November if you don't adapt.

Here are the key moments a London e-commerce brand needs to have circled on the calendar:

• -> Q4 (October-December): The big one. This is Black Friday, Cyber Monday, and the entire Christmas shopping season. Ad costs will skyrocket, but so will consumer intent. You need to have your campaigns, offers, and creative locked in by mid-October. I remember one e-commerce client in the apparel space; during the crucial Q4 shopping season, our campaigns generated a 691% return on ad spend.
• -> January Sales: The post-Christmas hangover means people are looking for bargains. This is a great time to clear old stock and acquire new customers with discount-led offers.
• -> Bank Holidays: Brits, and especially Londoners, love a Bank Holiday. It's a mini-event. Plan for three-day weekend sales. If you sell outdoor gear, promote "Bank Holiday Adventure" kits. If you sell homeware, it's "Bank Holiday DIY" offers.
• -> Summer (June-August): This can be a slump for some, but an opportunity for others. Travel, outdoor living, wedding season, festivals – if your product fits these themes, you can do very well while others pull back their spend.

Your performance will naturally ebb and flow with this calendar. Don't panic if your ROAS dips in a quiet period; instead, use that time to test new creative and build your retargeting audiences for the next peak.

Are You Actually Making Money? The Brutal Maths of London Ads

Let's be clear: advertising in London is expensive. You're competing with global brands with massive budgets. If you don't have a firm grip on your numbers, you can burn through cash with frightening speed and have nothing to show for it. Too many founders get excited by revenue figures without understanding their actual profitability.

The single most important metric for any e-commerce store is Return On Ad Spend (ROAS). It's a simple calculation: Revenue Generated from Ads / Ad Spend. If you spend £100 and make £300 in sales, your ROAS is 3x. But is a 3x ROAS good? It depends entirely on your profit margins.

If your product has a 70% profit margin, a 3x ROAS is fantastic. You spent £100, made £300 revenue, of which £210 is gross profit. Subtract your £100 ad spend, and you've got £110 in your pocket. Happy days.

But if your margin is only 40%, that same 3x ROAS is a problem. You spent £100, made £300 revenue, but your gross profit is only £120. Subtract the £100 ad spend, and you're left with just £20. And that's before accounting for overheads like staff, shipping, and software. You're likely losing money.

You MUST know your break-even ROAS. This is the point at which your ad spend is covered by your gross profit. The formula is simply 1 / Gross Margin %. For a 40% margin, your break-even ROAS is 1 / 0.40 = 2.5x. Any ROAS below 2.5x, and you are officially paying to give your products away. Knowing this number allows you to make unemotional, data-driven decisions about which campaigns to scale and which to kill.

Use the calculator below to find your break-even point and see how different ROAS figures impact your actual profit. This isn't a 'nice to have'; it's fundamental to running a sustainable business. If you find you're struggling to get above your break-even point, you may be facing the difficult truth that you have an issue with your traffic quality or conversion rates, not just your ad settings.

Your Blueprint for a Winning Campaign Structure

So how do you put all this together? A successful Meta Ads account isn't a chaotic mess of random campaigns. It's a clean, logical structure that mirrors your customer journey. This makes it easy to manage, diagnose problems, and allocate budget effectively.

I almost always recommend a structure built around the ToFu/MoFu/BoFu funnel we visualised earlier. This means separate, long-running campaigns for each stage. Don't create new campaigns every week; let them run continuously so the algorithm can gather data and properly learn.

Inside each campaign, you'll have different ad sets, and this is where you test your audiences. For your prospecting (ToFu) campaign, you might have one ad set for your best Lookalike audience, another for your strongest interest-based audience, and maybe a third testing a different London borough. For retargeting (BoFu), you'll have an ad set for 'Add to Carts' and another for 'Viewed Content'. This separation allows you to see exactly which audiences are performing and which are wasting money.

Then, within each ad set, you test your creatives. Always be testing. Test different images, videos, headlines, and calls to action. We've seen some SaaS clients get incredible results from simple UGC videos, and the same principle applies to e-commerce. A video of a real London customer unboxing your product can often outperform a slick, expensive studio shot because it feels more authentic.

The key is methodical testing. Only change one variable at a time. If you change the audience and the creative at the same time, you'll have no idea which change was responsible for the shift in performance.

I've detailed my main recommendations for you below:

When to Call in the Experts

Getting this right, especially in a market as fierce as London, is a full-time job. You're not just competing with other small businesses; you're up against ASOS, Selfridges, and countless global brands with dedicated performance marketing teams. It's a complex and ever-changing landscape.

If you're spending hours every week trying to decipher your Ads Manager, if your ROAS is stubbornly stuck below your break-even point, or if you simply don't have the time to implement the kind of structured testing I've described, it might be time to get help. An experienced agency or consultant has managed millions in ad spend across hundreds of accounts. They've already made the costly mistakes, so you don't have to. For many founders, this is a critical part of a broader performance marketing strategy that allows them to focus on their business.

The right partner won't just run your ads; they'll act as a strategic sounding board, helping you refine your offer, understand your numbers, and build a truly scalable customer acquisition engine. The process of finding the right fit, however, can be daunting, which is why having a clear framework for how to vet a potential Meta ads agency in London is so important.

Stop worrying about what time of day it is. Focus on the fundamentals: a deep understanding of your London customer, a compelling offer, a robust campaign structure, and a relentless commitment to testing. That's how you win.

If you'd like an expert pair of eyes on your current campaigns to identify your biggest opportunities for growth, we offer a completely free, no-obligation strategy consultation. We can walk through your account and give you some actionable advice you can implement straight away.

Hope that helps!