Sending speeds
How fast your messages go out on each plan. All figures are “up to” speeds: your effective speed is the lower of your plan’s speed and the carrier’s limit for your number type.
Each Flare plan has a maximum sending speed, and each carrier limits how fast a given type of number can send. SIPSTACK sends at whichever is lower. The tables below show the result for single-segment messages (up to 160 standard characters).
Messages per hour, up to
By plan and number type, for single-segment messages.
| Number type | Core | Pro | Ultra | Enterprise |
|---|---|---|---|---|
| US 10DLC local number¹ ² | 3,600 | 7,200 | 18,000 | 72,000+ |
| US toll-free | 3,600 | 7,200 | 10,800 | 10,800 |
| Canadian local number³ | 2,769 | 2,769 | 2,769 | 2,769 |
| Canadian toll-free | 3,600 | 7,200 | 10,800 | 10,800 |
10,000 messages in about…
The fastest a 10,000-message send can finish at the speeds above.
| Number type | Core | Pro | Ultra | Enterprise |
|---|---|---|---|---|
| US 10DLC local number¹ ² | ~2 h 47 min | ~1 h 23 min | ~33 min | ≤ 8 min |
| US toll-free | ~2 h 47 min | ~1 h 23 min | ~56 min | ~56 min |
| Canadian local number³ | ~3 h 37 min | ~3 h 37 min | ~3 h 37 min | ~3 h 37 min |
| Canadian toll-free | ~2 h 47 min | ~1 h 23 min | ~56 min | ~56 min |
Notes
- ¹ US 10DLC speed depends on your brand’s carrier trust score. These figures assume a vetted brand. Carriers can limit an unscored or low-trust brand to about 4 messages per second (14,400 per hour) or less, whatever your plan. Secondary (enhanced) vetting raises the carrier limit — how 10DLC trust scores affect speed.
- ² T-Mobile also applies a daily message cap to low-trust brands.
- ³ Carriers pace Canadian local numbers at just under 1 message per second, best-effort, on every plan. Use a toll-free number for faster Canadian sending.
All speeds are “up to” figures and are measured per segment. A message longer than 160 characters, or one with emoji or special characters (70 characters per segment), counts as several segments and sends proportionally slower. Quiet hours and daily send limits also stretch the time a send takes.
Need to send faster?
Compare Flare plans, or talk to sales about Enterprise speeds.