Can I send a WhatsApp campaign only to customers who owe me money?

Yes. Choose the overdue group in the campaign builder and the audience becomes every customer with a bill past its due date that isn't fully paid, resolved at send time.

If I schedule a campaign for next week, whose names does it use?

The ones that match on the day it sends. Computed groups are never stored with the campaign, so a customer who settles up before Friday is not messaged on Friday.

How many customers does the best-customers group contain?

Up to 50 — the biggest spenders by billed revenue over the last 365 days, excluding anyone with no billed revenue in that period.

What happens if no customer matches the group I picked?

The builder tells you nobody matches right now and the campaign is not launched, so you never get a success report for a send that reached nobody.

Can an opted-out customer end up in a segment?

No. Opt-outs are excluded before any group rule runs, and the builder reports how many were removed from the estimate.

Why is there no group for a custom spend threshold?

Because a threshold you type is a report, not an audience rule. Build the list from the sales performance report and send to a hand-picked audience instead.

Reference

Which customers a WhatsApp campaign goes to

The short answer

A campaign can go to all your customers, a list you tick by hand, or one of five computed groups: customers who owe you, customers who stopped buying, your 50 biggest spenders of the last year, customers whose reward points lapse within 30 days, and customers added this month. Computed groups are worked out again every time the campaign sends — they are never stored — so a scheduled or repeating campaign reaches today's matches, not the list that matched when you drafted it.

What each group means, exactly

No group invents its own definition. Each one reuses a rule the product already applies somewhere you can check it, which is why a campaign's reach and the report you looked at first cannot disagree.

Audience options in the campaign builder, with the rule behind each.
Group (as it appears in the builder)	Exactly who it selects	Where the rule comes from
Customers who owe you	Anyone with at least one bill past its due date that is not fully paid.	The same overdue test the receivables report and the dashboard's overdue card use.
Customers who stopped buying	Bought at least once, and nothing in the last 60 days. Contacts who never bought anything are left out.	The 60-day window belongs to the dashboard's own re-engage card, so both name the same people.
Your best customers	The 50 biggest spenders by billed revenue over the trailing 365 days. Anyone with no billed revenue in that year is excluded.	Counts issued, part-paid and paid invoices — a draft or cancelled bill is not a sale.
Points expiring soon	Customers whose oldest unspent reward points lapse within 30 days. Empty when your reward scheme has expiry switched off.	Walks the rewards ledger's own oldest-points-first logic, so the date it selects on is the date the points really lapse.
New customers this month	Everyone added since the 1st of the current month.	The customer's creation date.
All customers	Everyone reachable: has a phone number, is not a walk-in placeholder, has not opted out.	A literal audience — the reachability floor every other group starts from.
Pick customers	Exactly the customers you tick from your contact list.	A literal audience — stored with the campaign rather than computed.

The numbers behind the groups

Each threshold is a deliberate choice, not a default nobody looked at.

Stopped buying: 60 daysLong enough that a customer between festival purchases isn't called lapsed, short enough to still win them back.
Best customers: 50 customersThe cap is the point: an uncapped revenue sort is just everyone in a different order, at full marketing cost.
Spend window: 365 daysA full year, so a seasonal shop — a fireworks stall, a uniform tailor — isn't judged on its quiet months.
Points warning: 30 daysLong enough for the customer to plan a visit, short enough that the message is news rather than trivia.
Group resolved: At every sendIncluding each occurrence of a repeating campaign, which is what stops a monthly win-back messaging a frozen list forever.
Reach shown: Before you sendThe builder shows the estimated reach, how many opted-out customers were removed, the estimated cost and your remaining budget.

Rules that apply to every group

A group can narrow who gets a message. Nothing can widen it past what consent allows.

Opt-outs are removed first, always: Anyone who replied STOP is excluded before the group's own rule is applied, and the builder tells you how many were removed. A segment cannot smuggle an opted-out customer back into an audience.
No phone number, no message: Customers without a usable number are outside every audience, including All customers — so your reach estimate is a count of people who can actually receive it.
Walk-in counter sales are never messaged: The walk-in placeholder used for cash sales with no named customer is excluded from every audience by construction.
A computed group can't be hand-edited: Choosing a group and then also submitting a hand-picked list is refused rather than quietly merged. If you want a list, pick the list; if you want the rule, use the rule.
An empty group is told to you, not sent to: When nobody matches, the builder says so — Nobody matches this group right now — instead of launching a campaign to zero people and reporting success.
The estimate and the send use one definition: The count you approve and the recipients who get messaged come from the same query, so the number in the builder is not a friendlier version of reality.

Three things people expect that aren't true

These are the assumptions worth correcting before you schedule anything.

The recipient list is fixed when I create the campaign.
For a computed group it is resolved when the campaign sends. Draft a win-back today, schedule it for Friday, and it reaches whoever is lapsed on Friday. Only Pick customers stores a fixed list.
"Customers who stopped buying" includes contacts who never bought.
It doesn't, deliberately. Without that exclusion, every imported address book entry and one-off enquiry counts as lapsed and a win-back becomes a cold blast to strangers at marketing rates.
"Your best customers" means everyone above some spend.
It means the top 50 by trailing-year revenue. If you want a threshold instead, use a hand-picked list built from the sales performance report.

Which plan includes campaign audience groups

WhatsApp campaigns, and therefore every audience group here, are included on the Gold and Platinum plans. The Silver plan does not include WhatsApp campaigns.

The underlying data each group reads — overdue bills, purchase history, reward points, customer records — is on every plan including Silver. Gold is what adds the WhatsApp send. The gate is the same on cloud and on the Windows/Mac desktop app.

FAQs

Can I send a WhatsApp campaign only to customers who owe me money?: Yes. Choose the overdue group in the campaign builder and the audience becomes every customer with a bill past its due date that isn't fully paid, resolved at send time.
If I schedule a campaign for next week, whose names does it use?: The ones that match on the day it sends. Computed groups are never stored with the campaign, so a customer who settles up before Friday is not messaged on Friday.
How many customers does the best-customers group contain?: Up to 50 — the biggest spenders by billed revenue over the last 365 days, excluding anyone with no billed revenue in that period.
What happens if no customer matches the group I picked?: The builder tells you nobody matches right now and the campaign is not launched, so you never get a success report for a send that reached nobody.
Can an opted-out customer end up in a segment?: No. Opt-outs are excluded before any group rule runs, and the builder reports how many were removed from the estimate.
Why is there no group for a custom spend threshold?: Because a threshold you type is a report, not an audience rule. Build the list from the sales performance report and send to a hand-picked audience instead.