Cost per lead: Facebook Ads vs AI calling for UK small businesses.
Two channels, one question: which one puts a qualified conversation on your desk for less money? This page walks through the maths with real pricing so you can compare them side by side.
What cost per lead actually means
Cost per lead (CPL) is the total you spend on a channel divided by the number of leads it produces. A lead, for this comparison, is a real person who has expressed interest in hearing from you — not an impression, not a click, and not a form submission from someone who never answers their phone.
The distinction matters because Facebook Ads and AI calling produce different kinds of leads. A Facebook lead ad collects a name and phone number. An AI calling campaign produces a live conversation with a real decision-maker, transcribed and recorded. The quality of those two leads is not the same, and neither is the cost.
Facebook Ads: how the cost stacks up
Facebook lead ads in the UK typically cost between three pounds and fifteen pounds per form submission, depending on your industry, targeting and creative. B2B campaigns tend to sit at the higher end because the audience is smaller and more competitive.
But a form submission is not a conversation. Contact rates on Facebook leads vary widely — many submissions use autofill details that are out of date, or the person forgets they filled in the form by the time you call. If half your form submissions turn into an actual conversation, your real cost per conversation doubles.
- Ad spend per form submission — typically three pounds to fifteen pounds for UK B2B.
- Contact rate — varies, but reaching and speaking to the person behind a form submission often requires several follow-up attempts.
- Hidden costs — creative production, A/B testing, landing pages, and the time your team spends chasing cold form fills.
Facebook Ads are strong for brand awareness and retargeting. For generating a first conversation with a cold prospect, the economics are less clear.
AI calling: how the cost stacks up
With FoxEra Calls, you pay from 12p per connected minute. A connected minute is a minute where someone actually answered the phone and a conversation took place. You do not pay for calls that ring out, reach voicemail, or are declined.
A typical business-to-business cold call that reaches a decision-maker lasts between one and three minutes. That puts the cost of a single conversation at roughly 12p to 36p. Not every conversation produces a warm lead — some people are not interested — but every one is a real exchange with a real person, transcribed and logged.
- Cost per connected minute — from 12p, no subscription, no monthly fee.
- Cost per conversation — depends on call length, but a two-minute call costs roughly 24p.
- What you get — a recording, a transcript, and a logged outcome for every call. No chasing required; the conversation has already happened.
New accounts start with £7 of free calling credit. Use the AI calling cost calculator to estimate your campaign cost before you start, or read the full breakdown on how much AI calling costs.
Side-by-side: the numbers
Here is a simplified comparison for a campaign targeting 100 prospects:
- Facebook Ads — 100 form submissions at a mid-range cost per submission. Factor in a contact rate to see how many become real conversations. The total spend depends heavily on your industry and targeting.
- AI calling — 100 calls placed. Not all will connect, but you only pay for the ones that do. At a typical connect rate, you might reach 25 to 40 decision-makers, each conversation lasting one to three minutes. Your total cost is the connected minutes multiplied by 12p.
The key difference is what you are left with. Facebook gives you a list of names that still need chasing. AI calling gives you a list of outcomes: who is interested, who said no, who asked you to call back, and exactly what they said. That changes how your follow-up time is spent.
For a detailed cost estimate tailored to your campaign size, try the cost-per-minute breakdown or the full pricing page.
When to use each channel
Facebook Ads and AI calling are not mutually exclusive. Many businesses use both, but for different purposes:
- Facebook Ads work well for — brand awareness, retargeting website visitors, promoting events or offers, and reaching consumers. If your audience is on Facebook and responds to visual content, it is a strong channel.
- AI calling works well for — B2B prospecting, reaching decision-makers directly, qualifying interest in real time, and generating conversations with people who would never fill in a form. If you need to speak to someone specific, calling is faster.
For most UK small businesses doing B2B outreach, the cost per qualified conversation is lower with AI calling. For consumer-facing businesses with strong creative, Facebook Ads may produce volume more efficiently. The right answer depends on your market, your offer and what you consider a lead. Read our guide on the best way to get clients for a broader comparison of outreach channels.
Let your AI assistant run the comparison
If you use ChatGPT, Claude, Cursor or another AI assistant, you can connect it to FoxEra Calls and ask it to preview the cost of a calling campaign before you commit. Your assistant can upload a lead list, estimate the total connected minutes, and show you what the campaign would cost — all before anyone is phoned.
That makes it straightforward to compare: run your Facebook Ads numbers alongside an AI calling preview and see which channel gives you more conversations per pound. See how to connect ChatGPT or visit the developer guide for the setup.
Frequently asked questions
Is AI calling cheaper than Facebook Ads per lead?
For B2B outreach in the UK, the cost per qualified conversation is typically lower with AI calling. Facebook Ads can be more cost-effective for consumer-facing campaigns with strong creative. The right channel depends on your market.
How much does AI calling cost per lead?
You pay from 12p per connected minute. A typical B2B conversation lasts one to three minutes, putting the cost per conversation at roughly 12p to 36p. New accounts start with £7 of free calling credit.
Can I use both Facebook Ads and AI calling together?
Yes. Many businesses use Facebook Ads for brand awareness and retargeting, and AI calling for direct B2B outreach. The two channels complement each other and reach different audiences.
How do I calculate my cost per lead?
Divide your total spend on a channel by the number of leads it produced. For a fair comparison, define a lead consistently — a form submission and a live conversation are not equivalent. Use the cost calculator to estimate your AI calling spend.