Pistonlog sends SMS via Twilio. Each text costs SMS credits from your garage's balance (1 credit per 160 characters of the sent message), deducted at the moment the SMS is dispatched. If the gateway fails to send, the credits are automatically refunded.
What costs credits
| Action | Credits |
|---|---|
| A reminder SMS | 1 per 160 chars |
| A one-off reminder SMS | 1 per 160 chars |
| A jobcard share (customer portal) link sent via SMS | 1 per 160 chars |
| A review request sent via SMS | 1 per 160 chars |
| An appointment confirmation or rescheduling SMS | 1 per 160 chars |
| Email (any kind) | 0 |
Message composers cap SMS bodies at 320 characters, so a single send costs at most 2 credits: 1–160 characters is 1 credit, 161–320 is 2. The composer shows a live character count and credit cost as you type.
Topping up
Buy SMS credits from Workshop Settings → Manage Workshop Credits. Credits don't expire. Your current balance is shown at the top of that page, alongside your credit history.
What happens if you run out
If your balance hits zero mid-day, the next SMS attempt will fail and be logged in Reminder logs as failed with the error "Insufficient credits". Email reminders keep firing normally — they don't draw from this balance.
Why credits
Twilio charges per-message at carrier-set rates. Credits are how those costs land back on the garage's account without us reconciling Twilio bills in real time.