PPC (Pay-Per-Click) is online advertising where you pay each time someone clicks your ad. Major channels: Google Ads (search + Performance Max + Display + YouTube), Meta Ads (Facebook + Instagram), LinkedIn Ads, Microsoft / Bing, TikTok, Amazon, Reddit. Costs vary £0.10–£35+ per click depending on auction competition. PPC is right when (1) you can identify high-intent search behaviour, (2) you have a converting landing page, (3) you can measure CAC vs LTV.
You set up an account with the ad platform, define targeting (keywords, audience demographics, lookalike audiences, retargeting lists), upload creative (text ads, image ads, video ads), set a budget and bids. Each time the platform shows your ad and someone clicks, you pay.
Different platforms charge differently: Google Ads charges per click; Meta charges per impression but optimised toward action (CPC effectively); LinkedIn charges per click or per send (sponsored InMail); TikTok charges per impression with optimisation toward conversion event.
Google Search: high intent, expensive (London commercial CPCs £5–£35), high conversion. Best for clear buying intent.
Google Performance Max: ML-driven across Search + Display + YouTube + Gmail + Maps. Cheaper CPCs, lower control.
Meta (Facebook + Instagram): low intent, medium CPM, strong for visual products and retargeting. Right for D2C, lifestyle, hospitality.
LinkedIn: highest CPC (£6–£25 per click) but precise B2B targeting. Right for B2B SaaS, enterprise services.
TikTok: low intent, low CPC, high engagement. Right for D2C consumer brands with creative chops.
Microsoft (Bing): often half the CPC of Google for the same keywords; smaller audience but B2B-skewed.
London commercial-services CPCs are punishingly high because thousands of agencies are bidding on each other's keywords. 'PPC agency london' itself costs £18–£35 per click. 'web design london' £8–£16. 'SEO agency london' £14–£28.
Long-tail and borough-specific terms are 50–80% cheaper. 'web design shoreditch' might be £3–£6 vs £8–£16 for 'web design london'.
PPC works when: high-intent search exists ('plumber emergency london'), conversion path is short (landing page → form / purchase), CAC payback is <12 months, you can spend >£1,500/mo per channel for 60+ days.
PPC fails when: products require 9-month sales cycles (LinkedIn outbound or content-led works better), CAC payback is >18 months and you don't have funded burn capacity, landing page conversion is <1%, or organic SEO can capture the same traffic for less.
PPC: instant traffic, expensive per click, ends when you stop paying. SEO: slow ramp (6–12 months), compounding, cheaper per click in steady state.
For founders below £2m revenue: usually PPC first to get signal fast, SEO compounding alongside. Above £5m revenue: SEO is the moat, PPC is the catalyst.
"If your CAC payback is under 6 months and you have product-market fit, PPC scales linearly with budget. Most B2B SaaS doesn't have that math; for them content + SEO + LinkedIn outbound wins."