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Inbound Blacklist

The Inbound Blacklist allows you to block unwanted callers using flexible pattern matching. You can define rules that apply globally across all your phone numbers or target specific DIDs, and choose how blocked calls are handled.

Accessing the Blacklist​

Navigate to Inbound Blacklist in the sidebar. This feature is available to Owners and PBX Admins.

Match Types​

Each blacklist rule specifies a caller ID pattern and a match type that determines how the pattern is evaluated:

Match TypePattern ExampleMatches
Exact+14155551234Only that specific phone number
Prefix+1415Any number starting with +1415 (e.g., all San Francisco numbers)
Wildcard+1415555????Numbers matching the wildcard pattern (* = any characters, ? = single character)
tip

Use Prefix matching to block all calls from a specific area code or country code. Use Wildcard for more complex patterns.

Rejection Strategies​

When a call matches a blacklist rule, OPBX handles it according to the configured rejection strategy:

StrategyBehaviorCaller Experience
DropSilently hang up the callCaller hears nothing (call appears to fail)
RejectPlay a rejection message, then hang upCaller hears "Your call has been rejected"
TormentPlace the caller in a conference room with hold musicCaller is held in a loop with music for a configurable duration
note

The Torment strategy is useful for persistent spam callers. It ties up their line while playing hold music, discouraging further calls. You can configure the music timeout to control how long the caller is held.

Rule Scope​

Blacklist rules can be applied at two levels:

  • Global: The rule applies to all phone numbers (DIDs) in your organization. Any inbound call matching the pattern is blocked regardless of which number was dialed.
  • Per-DID: The rule only applies to specific phone numbers that you select. Calls to other numbers from the same caller are not affected.

Creating a Blacklist Rule​

  1. Navigate to Inbound Blacklist and click Add Rule
  2. Enter the Caller ID Pattern (the number or pattern to block)
  3. Select the Match Type (Exact, Prefix, or Wildcard)
  4. Choose the Rejection Strategy (Drop, Reject, or Torment)
  5. Set the Scope:
    • Toggle Global to apply to all DIDs
    • Or select specific phone numbers the rule should apply to
  6. Set the Status to Active
  7. Click Save

Managing Rules​

  • Toggle Status: Click the status toggle to enable or disable a rule without deleting it
  • Edit: Click a rule to modify its pattern, strategy, or scope
  • Delete: Remove a rule permanently

Blocked Call Logs​

OPBX maintains a log of all blocked calls. Access it from the Blocked Calls section on the Inbound Blacklist page.

Each log entry records:

  • Caller ID of the blocked caller
  • Phone number that was dialed
  • Which blacklist rule matched
  • Rejection strategy that was applied
  • Timestamp

Statistics​

The blacklist statistics panel shows aggregate data including:

  • Total number of blocked calls
  • Breakdown by rejection strategy
  • Most frequently blocked callers
warning

Blacklist rules are evaluated before call routing. If a caller matches a blacklist rule, the call is blocked immediately and never reaches any routing destination (extension, ring group, IVR, etc.).

How It Works​

When an inbound call arrives, OPBX checks the caller ID against all active blacklist rules for the organization:

  1. First, global rules are checked (rules that apply to all DIDs)
  2. Then, per-DID rules are checked for the specific phone number that was dialed
  3. If any rule matches, the configured rejection strategy is executed
  4. If no rules match, the call proceeds to normal routing

Next Steps​