If you make outbound calls professionally, knowing the threshold that triggers spam detection is essential.
Call Volume Thresholds
Under 50 Calls Per Day: Safe Zone
Staying below 50 daily calls per number is generally safe.
50-100 Calls: Moderate Risk
Other factors like answer rates become critical.
100-200 Calls: High Risk
Spam detection algorithms actively analyze your behavior.
Over 200 Calls: Danger Zone
Dramatically increases chances of being flagged.
500+ Calls: Almost Certain Flag
Virtually guarantees spam classification.
Factors Beyond Volume
Answer Rate
- Below 5% raises red flags
- Very short calls suggest robocalling
Consumer Complaints
User reports carry significant weight in spam detection.
Number History
Long-standing numbers with clean history have more tolerance.
How Detection Algorithms Work
STIR/SHAKEN (US)
Authenticates caller ID and assigns attestation levels.
Carrier Analytics
Major carriers share data for cross-carrier spam identification.
Best Practices
- Keep each number under 50 calls daily
- Rotate based on time zones and campaigns
- Warm up new numbers gradually
- Monitor reputation regularly
FAQ
How many calls before being flagged?
No universal number, but staying under 50/day significantly reduces risk.
Can I recover a flagged number?
Yes, but it takes 30-90 days. Stop using it and register with carrier reputation services.










