SMS Credits & Billing
The SMS add-on includes 300 message segments per month for $15/month. Credits are tracked automatically and refill on your billing cycle.
What Counts as a Segment
SMS is billed by segment, not by message. A single text can use one or more segments depending on its length and character type:
| Message Type | Characters Per Segment | When You’ll See It |
|---|---|---|
| Standard text (GSM-7 encoding) | 160 characters (153 in multi-part messages) | Plain English text with basic punctuation |
| Unicode text (UCS-2 encoding) | 70 characters (67 in multi-part messages) | Any message containing an emoji or non-Latin character |
A single emoji anywhere in the message switches the entire text to Unicode encoding, which drops the per-segment limit to 70 characters.
Typical message costs
Most notifications sent by Service Invoice Pro use 2 segments per send because the message body includes your business name, an invoice or estimate number, a payment link, and the required opt-out footer:
| Notification | Typical Segments |
|---|---|
| Invoice payment link | 2 |
| Estimate review link | 2 |
| Review request | 2 |
| Portal invite | 1–2 |
| On My Way (default message) | 1 |
| On My Way (custom message with long template) | 2+ |
Plan on roughly 150 sends per month with the included 300 segments. If you customize the On My Way template, longer messages will cost more.
Checking Your Balance
Go to Settings → SMS Notifications. The credits widget at the top shows:
- Remaining — how many segments you have left this cycle
- Monthly — your total monthly allocation (300)
- Next Refill — the date your credits reset
The widget turns amber when credits drop below 50 and red when credits reach 0.
When Credits Refill
Credits automatically refill to 300 on your monthly billing date when your SMS subscription renews through Stripe. Unused credits do not roll over to the next month.
When Credits Run Out
If your credit balance reaches 0, SMS sending stops until your next billing cycle. Your toggles, settings, and customer phone numbers stay in place — sending will resume automatically once credits refill.
If you need more credits before your next refill, contact support.
Sending Limits
In addition to your monthly credit balance, Service Invoice Pro enforces sending limits to prevent abuse and protect deliverability:
| Limit | Cap | Resets |
|---|---|---|
| Per user, per day | 50 messages | At midnight UTC |
| Per user, per hour | 15 messages | Hourly |
| Per organization, per day | 200 segments | At midnight UTC |
| Per recipient phone, per 24 hours | 3 messages | Rolling 24-hour window |
If you hit a limit, the send fails with an error message and your credits are refunded immediately. These limits reset automatically — there’s no action required on your part.
Failed Sends and Refunds
Credits are reserved before a text goes to the phone carrier and reconciled afterward:
- Send rejected before reaching the carrier (invalid number, rate limit, customer opted out): credits refunded instantly.
- Send accepted by the carrier but delivery fails later (unreachable phone, landline, etc.): credits refunded automatically when the failure is reported back, usually within a few minutes.
- Send succeeded but message was longer than estimated (e.g. customer name pushed it over a segment boundary): the difference is charged from your balance.
You can verify refunds by watching the Remaining counter on the SMS settings page — it updates in real time.
Related
- SMS Notifications Overview — what the add-on includes
- Enabling SMS — how to activate the add-on
- SMS Troubleshooting — common errors and how to resolve them
- Billing & Plans — manage your subscription