Cost Optimization¶

Azure Communication Services (ACS) uses a consumption-based pricing model, meaning you only pay for what you use. This document outlines the best practices for managing and optimizing your ACS costs.

ACS Pricing Model Overview¶

Costs are calculated differently for each communication channel:

Phone Number Cost Management¶

Phone numbers carry a fixed monthly cost, regardless of usage.

• Cleanup Unused Numbers: Regularly audit your phone numbers in the Azure Portal and release those that are no longer needed.
• Consolidate Traffic: Use a single number for multiple campaigns or departments where possible, especially for toll-free numbers.

Optimizing SMS Costs¶

SMS costs are based on the number of message segments sent.

• Message Segmentation: Standard SMS messages are limited to 160 characters (GSM-7) or 70 characters (Unicode). Be aware that long messages are split into multiple segments, increasing the cost.
• Avoid Unicode: Whenever possible, use only GSM-7 characters to maximize the characters per segment and reduce costs.
• Opt-out Handling: Implement opt-out logic (e.g., "Reply STOP to unsubscribe") to avoid sending messages to users who do not want them, which reduces waste and ensures regulatory compliance.

graph TD
    A[Start: Compose SMS] --> B{Contains Unicode?}
    B -- Yes --> C[Limit: 70 chars/segment]
    B -- No --> D[Limit: 160 chars/segment]
    C --> E[Calculate Total Segments]
    D --> E
    E --> F[Total Cost = Segments * Rate]

Email Tier Selection¶

ACS offers multiple email sending tiers based on volume. Choose the tier that best fits your expected monthly sending volume.

Video and Voice Cost Optimization¶

Calling costs are based on the number of participant-minutes.

• Resolution and Bandwidth: While you don't pay more for high resolution, using it consumes more bandwidth, which can increase data egress costs for your Azure environment.
• Disconnect Idle Participants: Implement logic to automatically disconnect participants from a call or chat thread after a period of inactivity to prevent accidental overcharging.

Cost Monitoring with Azure Cost Management¶

Use Azure Cost Management to track and analyze your ACS spending.

• Budgets: Set up budgets for your ACS resource group and configure alerts to notify you when spending reaches a certain threshold.
• Tags: Apply tags (e.g., Environment, Department, Project) to your ACS resources to breakdown costs by business unit or environment.
• Cost Analysis: Use the Azure Portal's cost analysis tools to identify which channels (e.g., SMS vs. Calling) are driving the most spend.

Why This Matters¶

Because ACS billing is consumption-based, cost scales directly with how you send. Small design choices — Unicode SMS, idle participants left connected, or unused rented numbers — compound into avoidable monthly spend. Understanding the per-channel pricing model is the prerequisite for controlling it.

Recommended Practices¶

• Audit and release unused phone numbers, and consolidate traffic onto fewer numbers where regulations allow.
• Keep SMS within GSM-7 characters to maximize characters per segment, and honor opt-out to avoid wasted sends.
• Choose the email tier that matches expected monthly volume rather than over-provisioning.
• Disconnect idle call and chat participants automatically to stop accidental participant-minute charges.
• Set Cost Management budgets with alerts, tag resources by environment and department, and review channel-level cost analysis regularly.

Common Mistakes / Anti-Patterns¶

• Sending Unicode SMS when GSM-7 would suffice, silently doubling segment counts.
• Leaving unused toll-free or international numbers rented, incurring fixed monthly charges.
• Running production without budgets or alerts, so overspend is discovered only on the invoice.
• Never disconnecting idle participants on long-lived calls or threads.

Validation Checklist¶

• [ ] Unused phone numbers are audited and released on a schedule.
• [ ] SMS payloads avoid unnecessary Unicode and respect opt-out.
• [ ] The selected email tier matches actual volume.
• [ ] Idle participants are disconnected automatically.
• [ ] Budgets, cost alerts, and resource tags are configured.

See Also¶

• Operations: Cost Optimization
• Scaling Best Practices

Sources¶

• ACS Pricing Details
• Azure Cost Management
• SMS Message Segmentation