Usage metrics explained
Voice minutes
Voice minutes are the total time your AI receptionist spends on the phone with callers. Each call contributes to your monthly voice minute total from the moment the AI answers to when the call ends. Hold time and transfer time before the AI hands off to a human are also counted.Outbound call attempts
Outbound call attempts are the calls LobbyStack places on your behalf — most commonly for missed-call follow-up, where the AI calls back a caller who hung up before leaving a message. Each dial attempt counts as one outbound call attempt, regardless of whether the call is answered.Alert SMS segments
Alert SMS segments are the text message segments sent as call summary notifications. After a call, LobbyStack can send you (or your team) an SMS summarizing who called and what they needed. Standard SMS messages can be up to 160 characters; longer messages are split into multiple segments, and each segment counts separately.Two-way AI SMS segments (Pro add-on)
Two-way AI SMS segments are the text message segments exchanged in full AI-driven SMS conversations with your callers. This is distinct from alert SMS: two-way AI SMS lets callers text your business number and receive intelligent replies from the AI. Each segment sent or received in those conversations counts toward your two-way AI SMS usage. This feature is available as a paid add-on on the Pro plan.Knowledge storage
Knowledge storage is the total size of all content you have added to your knowledge base — uploaded documents, written FAQs, and any website content you have imported. LobbyStack uses this content to answer caller questions accurately.What happens when you reach your quota
The Free plan does not have overage billing. When you reach your included voice minutes, outbound call attempts, or alert SMS segments, that usage type stops for the rest of the billing period. Your calls may stop being answered when voice minutes are exhausted. Upgrade to Pro to prevent interruptions and unlock usage-based overage.
Overage rates
| Usage type | Included on Free | Included on Pro | Overage rate (Pro) |
|---|---|---|---|
| Voice minutes | 10 min | 80 min | $0.18 per minute |
| Outbound call attempts | 2 | 20 | $0.02 per attempt |
| Alert SMS segments | 10 | 50 | $0.02 per segment |
| Two-way AI SMS segments | Not available | Add-on: 19 setup | $0.03 per segment |
| Knowledge storage | 100 MB | 2 GB | No overage — storage is capped |
Knowledge storage does not have an overage rate. If you reach your storage limit, you will need to remove existing content before adding more. Pro includes 2 GB, which is enough for thousands of documents and FAQ entries for most service businesses.
How overage charges appear
On Pro, overages accumulate throughout the month and are billed at your next monthly renewal. You will see a line item for each usage type that exceeded your included quota on your billing statement in the Polar customer portal. To open your billing statement, go to Settings → Billing and select Manage subscription.Viewing your current usage
You can check how much of your monthly quota you have used at any time from the dashboard.Review the usage section
The Usage section shows a progress bar for each metric — voice minutes, outbound call attempts, alert SMS segments, and knowledge storage — along with how much of your included quota you have consumed this period.