The formula
Customer acquisition cost = Total acquisition spend / New guests acquired
Value to cost ratio = Lifetime gross profit per guest / Acquisition cost
Why the formula insists on new guests only: the moment returning regulars who happened to see an ad are counted as acquired, the cost per guest collapses to a flattering fiction and every channel looks efficient. Net new guests is the honest denominator, which is why properly measured acquisition costs look higher than platform dashboards suggest. Industry studies that isolate net new guests put paid acquisition at roughly $27 for quick service, $83 for fast casual, $125 for casual dining and close to $180 for fine dining. The second formula is the real verdict: a guest should return at least three times their acquisition cost in lifetime gross profit before a channel deserves to be scaled.
How to use it, with an example
- Pick one period or one campaign and hold the dates fixed for both spend and guests.
- Add the three kinds of spend: the ads themselves, the margin given away on first-visit offers, and the other fees of acquisition such as influencer payments and first-order platform commissions.
- Count new guests from your POS, reservation or online ordering records: first-time guests only, not total covers and not ad clicks.
- Add the lifetime gross profit per guest if you know it, and read the cost per guest, the guests each $100 buys, and the value to cost ratio.
Worked example: A fast casual restaurant spends $1,500 on paid social and search in a month, gives away $600 of margin on a first-visit offer, and pays $400 in influencer and platform fees, a total of $2,500. The records show 85 genuinely new guests, so acquisition cost is $2,500 / 85 = $29.41 per new guest, and every $100 of spend buys about 3.4 guests. Against fast casual paid benchmarks near $83 for a net new guest, that is efficient acquisition, provided those guests return. The calculator above is prefilled with these same numbers, so you can see the breakdown before entering your own campaign.
Acquisition cost stays honest only when spend and first visits are recorded in the same place, campaign by campaign. With Odoo for Restaurants, campaigns, leads and first orders can be tracked through Odoo CRM against the guest record the POS creates, so the new guest count comes from the system instead of an ad platform grading its own homework.
Common mistakes
- Counting returning guests as acquired. The single biggest distortion. An ad clicked by a regular on their usual Friday visit acquired nobody, and including them makes a weak channel look strong. Define a new guest as no visit and no order in your records before the campaign, and hold the line.
- Forgetting the cost of the offer. A “free appetizer for new guests” campaign costs the food, not nothing, and first-order marketplace commissions are acquisition spend whether they are labelled marketing or not.
- Judging CAC against the first check. A $29 guest who spends $32 on visit one looks marginal until their second, fifth and twentieth visits are counted. Acquisition is an investment repaid across the relationship, which is why the ratio against lifetime profit, not first-visit spend, decides whether to scale a channel.
- Blending every channel into one average. Paid social, search, marketplaces and word of mouth have wildly different costs. One blended CAC hides the channel quietly losing money behind the channel printing it. Calculate per channel, using guest source data your system actually captures, a capability worth checking when reviewing what restaurant POS software tracks.
- Trusting the ad platform’s own numbers. Platforms count conversions generously, including people who would have come anyway. Your POS count of first-time guests is slower and less flattering, and it is the only denominator that connects spend to covers, as anyone comparing systems in how to choose a restaurant POS system should insist on being able to export.
- Spending to acquire guests the kitchen cannot keep. Acquisition into a bad first experience buys expensive one-time visitors. Fix speed, accuracy and recovery of unhappy guests before scaling spend, or the budget simply rents a bigger audience for the same leaky bucket.
FAQs
What is a good customer acquisition cost for a restaurant?
Measured on net new guests, paid acquisition typically runs about $27 for quick service, $83 for fast casual, $125 for casual dining and up to $180 for fine dining, while organic channels such as search, social and referrals cost far less. Good is ultimately relative to your guest: any CAC under a third of the guest’s lifetime gross profit is healthy economics, whatever the benchmark table says.
Which costs count toward acquisition spend?
Everything spent to win first visits: paid ads, the food cost of first-visit offers and discounts, influencer and creator fees, marketplace commissions on first orders, and the share of agency or freelance time spent on acquisition campaigns. General brand costs and retention marketing to existing guests do not belong in the figure.
Why is my platform-reported CAC lower than this calculation?
Because platforms count anyone who saw or clicked an ad and later ordered, including regulars who were coming anyway, and they rarely see the cost of your offers and fees. Dividing total true spend by verified first-time guests is stricter, and the honest number is almost always higher.
How can a restaurant lower its acquisition cost?
Shift mix toward channels with memory: search presence, referrals, and capturing first-party guest data so the second visit costs an email instead of another ad. Tighten ad targeting to lookalike audiences built from your best guests, and make the first-visit offer earn a captured phone number or loyalty signup, so the expensive first contact buys a cheap channel for every visit after.
How often should CAC be calculated?
Per campaign, and monthly as a rolling figure per channel. Acquisition costs move with auction prices, seasonality and offer fatigue, and a channel that was efficient in spring can be the most expensive seat in the house by December. Monthly discipline catches the drift while the budget can still be moved.
