Before you publish a Journey campaign, Bookboost shows you roughly what it would cost to deliver that campaign by SMS over a month. It is there so you find out the price before the campaign starts sending, not after. The figure is an estimate, not a quote, and this article explains what goes into it and why your invoice will differ.
Where to find it
Open a Journey campaign under Campaigns.
Go to the 4. Review & Publish step.
Look for the SMS costs section, below Title & Categories.
The section is on Journey campaigns only, and it only appears once the campaign has an SMS message body written. Until there is a message to measure, there is nothing to price, so the section is not shown.
It reads something like this:
Sending this campaign via SMS to every new reservation will cost around 3.84€ ~ 4.69€ per month.
What the estimate is actually telling you
Read the sentence carefully: it prices the campaign as if every message went out by SMS. It is not a forecast of your next invoice.
That matters because most campaigns do not send everything by SMS. If the campaign is set up as Omnichannel, Bookboost tries your channels in the order set under Channel Preferences, so a guest with a WhatsApp number may never receive an SMS at all. The estimate deliberately ignores that and prices the SMS-only case, which makes it a useful ceiling rather than a prediction.
The figure is a range, not a single number, and it is expressed per month because a Journey keeps sending for as long as it is active.
The three things it is based on
The section lists its own inputs on screen:
The length of the message. SMS is billed per part, not per message. A longer message is split into more parts and costs more. You can see the split on the message preview to the right of the Review & Publish step, where Parts and Characters are shown for the SMS version.
The average amount of reservations made per month, including canceled. Cancelled reservations are counted, because a campaign may already have sent before the cancellation came through.
The amount of reservations made last month. Recent volume, so the estimate follows your seasonality rather than a long-run average.
Why your invoice will differ
Bookboost says this on screen too, and it is the most common source of confusion:
Channel preferences. Every message that goes out over WhatsApp or email instead of SMS costs you nothing in SMS. See Journey campaign advanced settings for the settings that affect which channel is used.
Audience settings. The estimate assumes the audience as configured right now. Narrow the audience and the real cost drops.
Reservation volume. The estimate projects from last month. A busier or quieter month moves the real figure.
Suppression. Messages that are never sent are never charged. First per day and the 30-minute window on update triggers both suppress sends that the estimate has already counted.
Bringing the cost down
The section suggests two levers, and both work well in practice:
Use WhatsApp instead. WhatsApp is materially cheaper than SMS for most properties. Add it as a channel and rank it above SMS under Channel Preferences, so SMS becomes the fallback rather than the default.
Target a specific segment. A campaign aimed at all guests is the most expensive version of that campaign. An audience filter that narrows it to the guests who actually need the message cuts the cost proportionally.
A third lever the section does not mention: shorten the message. Because SMS is billed per part, trimming a message from two parts to one halves its cost. Keep an eye on the Parts counter on the preview while you write, and remember that long links push you over the boundary, leaving Shorten links on under Advanced helps here as well as with click tracking.
Getting help
Open Talk to Us in the left menu of the platform, or email support@bookboost.io. Tell us the campaign name and the figure you are seeing, and we can walk through what is driving it.