Area Code 940: Coverage, Cities, and More

Master area code 940 in Texas with this comprehensive developer guide covering 79 cities, 23 counties, and 10-digit dialing requirements in North Texas. Learn about Denton, Wichita Falls, Central Time zone coverage, FCC and NANPA regulations, 988 Suicide & Crisis Lifeline implementation, and best practices for building telephony applications serving the 940 area code region.

Area code 940 serves north-central Texas as part of the North American Numbering Plan (NANP), covering approximately 2.6 million residents across the Denton and Wichita Falls metropolitan areas. This guide provides developers with essential information about geographic coverage, 988 implementation, mandatory 10-digit dialing (effective October 24, 2021), Central Time zone (CT/GMT-6) considerations, and practical integration strategies for SMS, voice, and telephony systems.

What You'll Learn:

• Geographic coverage: 79 cities, 23 counties, and 2.6 million population in Texas
• Major cities: Denton (166,000+), Wichita Falls (102,000+), Gainesville, Mineral Wells
• Time zone: Central Time (CT/GMT-6) for all 940 area code locations
• 10-digit dialing mandate and 988 implementation timeline (2021–2022)
• FCC and NANPA regulatory framework for telecommunications compliance
• STIR/SHAKEN caller ID authentication and TCPA compliance requirements
• Historical context: 1997 split from area code 817
• Developer best practices with code examples in Python and JavaScript
• Current status: No overlay planned, numbers not in jeopardy

Prerequisites: Basic understanding of NANP structure, E.164 phone number formatting, and telecommunications APIs.

Where is Area Code 940? Geographic Coverage Map

Area code 940 is located in Texas, covering the north-central region of the state. Area code 940 encompasses urban centers, suburban communities, and rural areas across the Denton and Wichita Falls metropolitan regions. This area code spans 23 counties and serves 79 cities, providing service to approximately 2,635,129 residents.

Time Zone: All area code 940 locations are in the Central Time zone (CT), which is GMT-6 (or GMT-5 during Daylight Saving Time). This is critical for developers scheduling calls, SMS messages, and ensuring TCPA compliance with time-of-day restrictions.

Economic Context: The region's economy is anchored by several key industries. According to the Texas Comptroller's 2024 Northwest Region report, the largest employment sectors include restaurants and food services (16,798 employees), elementary and secondary schools (16,465 employees), and healthcare services (10,782+ hospital employees). The region shows specialization in manufacturing (lime/gypsum products, clay products, footwear), oil and gas extraction, cattle ranching, and electric power generation. Average annual wages in the region were $49,389 in 2022, with median household income at $54,037 (2021). Key employers include Sheppard Air Force Base (Wichita Falls), University of North Texas (Denton), and major healthcare systems.

Current Status: Area code 940 is not currently in jeopardy and will not run out of numbers before a change can be made, with no relief planning currently underway. There are currently no overlays – this is the only area code for these geographic regions.

Area Code 940 Cities: Complete List of Major Cities

While Denton is often the first city associated with area code 940, the coverage area encompasses a much broader range of locations across Texas. Knowing these locations helps when developing location-aware applications or targeting specific demographics.

Major Cities by Population (2024–2025 data):

Denton County: Home to the University of North Texas and Texas Woman's University, Denton is a major hub for education and culture with a median age of 31 and median household income of $73,719 (2023). The city's population is 54.6% White, 25.1% Hispanic, and 11.5% Black. Other significant cities in Denton County within area code 940 include Sanger, Krum, Pilot Point, Justin, and Aubrey.

Wichita County: Home to Wichita Falls (population 102,372 in 2024), a city with a strong military presence due to Sheppard Air Force Base. The racial composition includes 58.4% White, 22.4% Hispanic, and 12.5% Black, with a median household income of $58,568 (2023). Other notable cities in Wichita County include Burkburnett and Iowa Park.

Additional Counties and Cities: Area code 940 extends into numerous other counties, including Cooke, Palo Pinto, Wise, Young, Parker, Wilbarger, Clay, Archer, Jack, Childress, Haskell, Hardeman, Baylor, Knox, Throckmorton, and Stonewall. Consider this breadth of coverage when designing applications that interact with phone numbers.

Latitude and Longitude: Pinpointing the 940 Area

General geographic descriptions are helpful, but precise coordinates are necessary for developers working with mapping or location-based services. The approximate center of the 940 area code is:

• Latitude: 33.21484
• Longitude: -97.13307

These coordinates provide a central reference point, but remember that the 940 area code covers a wide expanse – account for this range when developing location-aware applications.

Mapping Example (JavaScript with Leaflet):

// Display area code 940 center on a map
const map = L.map('map').setView([33.21484, -97.13307], 8);
L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png').addTo(map);
L.marker([33.21484, -97.13307]).addTo(map)
  .bindPopup('Area Code 940 Center<br&gt;North-Central Texas');

10-Digit Dialing and Regulatory Information

Understanding the dialing patterns and regulatory framework of area code 940 is essential for building telephony applications. Correct dialing procedures ensure your application connects calls accurately and efficiently.

10-Digit Dialing Mandatory for Area Code 940

As of October 24, 2021, 10-digit dialing became mandatory for all calls within area code 940. This change, implemented by the FCC to accommodate the nationwide 988 Suicide & Crisis Lifeline, requires callers to dial both the area code and the 7-digit phone number, even for local calls. This is critical for developers to incorporate into their applications – failing to implement 10-digit dialing will result in failed calls. Design your applications to handle the most current dialing patterns.

Implementation Timeline:

• April 24, 2021 – October 24, 2021: Permissive dialing period where 10-digit dialing was available but 7-digit dialing still completed calls
• October 24, 2021: Mandatory 10-digit dialing began – 7-digit calls no longer completed
• July 16, 2022: 988 became operational nationwide as the three-digit code for the Suicide & Crisis Lifeline (the 10-digit number 1-800-273-TALK (8255) remains operational)

Standard Dialing Formats:

• Local calls: 940-XXX-XXXX (10 digits required)
• Long distance: 1-940-XXX-XXXX (1 + 10 digits)
• International format (E.164): +1-940-XXX-XXXX

Technical Implementation Requirements:

1. Input Validation: Accept 10-digit minimum (area code + number)
2. Format Normalization: Convert all input to E.164 format (+19407XXXXXX) for storage
3. Display Formatting: Present numbers in user-friendly formats like (940) XXX-XXXX
4. Error Handling: Reject 7-digit inputs with clear error messages

Valid vs Invalid Formats:

Phone Number Validation Code Examples:

Python with phonenumbers library:

import phonenumbers
from phonenumbers import NumberParseException

def validate_940_number(phone_input):
    """Validate and format area code 940 phone numbers"""
    try:
        # Parse with US region hint
        parsed = phonenumbers.parse(phone_input, "US")

        # Validate the number
        if not phonenumbers.is_valid_number(parsed):
            return {"valid": False, "error": "Invalid phone number"}

        # Check if it's area code 940
        formatted = phonenumbers.format_number(
            parsed,
            phonenumbers.PhoneNumberFormat.E164
        )

        if not formatted.startswith("+1940"):
            return {"valid": False, "error": "Not area code 940"}

        return {
            "valid": True,
            "e164": formatted,  # +19407XXXXXX
            "national": phonenumbers.format_number(
                parsed,
                phonenumbers.PhoneNumberFormat.NATIONAL
            ),  # (940) XXX-XXXX
            "international": phonenumbers.format_number(
                parsed,
                phonenumbers.PhoneNumberFormat.INTERNATIONAL
            )  # +1 940-XXX-XXXX
        }
    except NumberParseException as e:
        return {"valid": False, "error": str(e)}

# Example usage
result = validate_940_number("940-382-2200")
print(result)
# Output: {'valid': True, 'e164': '+19403822200',
#          'national': '(940) 382-2200',
#          'international': '+1 940-382-2200'}

JavaScript with libphonenumber-js:

import { parsePhoneNumber, isValidPhoneNumber } from 'libphonenumber-js';

function validate940Number(phoneInput) {
    try {
        // Parse with US country code
        const phoneNumber = parsePhoneNumber(phoneInput, 'US');

        // Validate
        if (!phoneNumber || !phoneNumber.isValid()) {
            return { valid: false, error: 'Invalid phone number' };
        }

        // Check area code 940
        const e164 = phoneNumber.format('E.164');
        if (!e164.startsWith('+1940')) {
            return { valid: false, error: 'Not area code 940' };
        }

        return {
            valid: true,
            e164: e164,  // +19407XXXXXX
            national: phoneNumber.formatNational(),  // (940) XXX-XXXX
            international: phoneNumber.formatInternational()  // +1 940 XXX XXXX
        };
    } catch (error) {
        return { valid: false, error: error.message };
    }
}

// Example usage
const result = validate940Number('(940) 382-2200');
console.log(result);

Regular Expression for Quick Validation:

// Regex for 940 area code (multiple formats)
const regex940 = /^(\+1|1)?[\s.-]?\(?940\)?[\s.-]?[0-9]{3}[\s.-]?[0-9]{4}$/;

// Test examples
console.log(regex940.test('+1-940-382-2200'));  // true
console.log(regex940.test('940-382-2200'));      // true
console.log(regex940.test('(940) 382-2200'));    // true
console.log(regex940.test('382-2200'));          // false (7-digit)

Regulatory Framework: The Role of NANPA and the FCC

The North American Numbering Plan Administration (NANPA) manages area codes and numbering resources, while the Federal Communications Commission (FCC) provides oversight and establishes telecommunications regulations. NANPA allocates area codes, assigns prefixes to telecommunication providers, and oversees the overall numbering plan. Developers should be aware of NANPA's role and consult their resources for the latest information on numbering plan updates and regulations. This information is vital for maintaining compliance and ensuring your applications function properly. For example, NANPA's guidelines on number pooling – where numbers are assigned in smaller blocks than the traditional 10,000 – can impact how you acquire and manage phone numbers for your applications. This is particularly relevant if your application requires a large volume of numbers.

STIR/SHAKEN Caller ID Authentication Requirements

If you're building telephony applications that originate or transmit calls, you must comply with FCC STIR/SHAKEN requirements for caller ID authentication. STIR/SHAKEN (Secure Telephone Identity Revisited / Signature-based Handling of Asserted Information Using toKENs) digitally validates caller ID information to combat spoofed robocalls.

Key Compliance Requirements for Developers (as of 2024–2025):

1. Implementation Mandate: Voice service providers must implement STIR/SHAKEN in IP networks (required since June 30, 2021 for most providers)
2. Authentication Signing: Calls must be digitally "signed" as legitimate by originating carriers
3. Robocall Mitigation Database: All providers must file certifications in the Robocall Mitigation Database
4. Gateway Provider Requirements: U.S.-based gateway providers receiving calls from foreign sources must implement STIR/SHAKEN
5. Non-IP Network Transition: Providers using older technology must upgrade to IP or develop alternative authentication solutions

For Application Developers:

• Work with STIR/SHAKEN-compliant telephony providers (Twilio, Vonage, Plivo)
• Ensure your Service Provider Code (SPC) token is properly configured
• Implement proper caller ID handling in your applications
• Do not spoof or manipulate caller ID information

TCPA Compliance Requirements

The Telephone Consumer Protection Act (TCPA) regulates telemarketing calls, autodialed calls, and text messages. Developers building applications that send SMS or make calls to area code 940 numbers must comply with TCPA regulations.

Critical TCPA Requirements (2025 Updates):

1. One-to-One Consent Rule (Effective January 27, 2025): Obtain explicit consent for each specific seller/caller, not blanket consent from lead generators
2. Prior Express Written Consent: Required for autodialed calls, prerecorded messages, and text messages to wireless numbers
3. Consent Revocation (New April 11, 2025 Rules): Process opt-out requests within 10 business days (reduced from 30 days)
4. Clear Disclosure: Clearly identify the caller and purpose of the call
5. Do Not Call Registry: Honor National Do Not Call Registry and maintain internal do-not-call lists
6. Time Restrictions: No calls before 8 AM or after 9 PM in the recipient's local time zone (Central Time for most 940 numbers)

TCPA Compliance Checklist for Developers:

• ✅ Implement consent tracking and documentation systems
• ✅ Provide clear opt-out mechanisms (reply STOP for SMS)
• ✅ Process opt-outs within 10 business days
• ✅ Maintain audit logs of all consent and opt-out actions
• ✅ Respect time-zone restrictions (area code 940 is Central Time)
• ✅ Implement rate limiting to avoid spam classification
• ✅ Provide accurate caller ID information
• ✅ Train customer service teams on TCPA requirements

Penalties: TCPA violations can result in $500–$1,500 per violation, with class action lawsuits common (507 TCPA class actions filed in Q1 2025, a 112% increase year-over-year).

History and Evolution: From 817 to 940

Area code 940 was created on July 7, 1997, as a split from the existing 817 area code. This split was necessary due to increasing demand for phone numbers in the rapidly growing north-central Texas region. The proliferation of cell phones, fax machines, and internet connections contributed to this demand. Understanding this historical context helps developers appreciate the dynamic nature of the telecommunications landscape and the ongoing need for efficient number management. As the demand for phone numbers continues to evolve, developers should anticipate future changes and design their applications with flexibility and adaptability in mind.

Practical Implications for Developers: Building Robust Applications

When developing applications that interact with the telephone network, consider these best practices:

Validate User Input: Always validate user-provided phone numbers to ensure they conform to the 1+10D format. Use libraries like libphonenumber (Python: phonenumbers, JavaScript: libphonenumber-js) instead of writing custom regex.

Normalize to E.164: Store all phone numbers in E.164 format (+19407XXXXXX) in your database for consistency and international compatibility.

Display in User-Friendly Formats: Present numbers as (940) XXX-XXXX for better readability while maintaining E.164 in storage.

Handle Dialing Variations: While 1+10D is the standard, some users might still attempt to dial using 7 digits or other variations. Your application should gracefully handle these scenarios and provide clear feedback to the user.

Implement Proper Error Messages: When validation fails, provide specific, actionable error messages like "Please enter a 10-digit phone number including area code" rather than generic "Invalid input."

Stay Updated: Telecommunication regulations and dialing patterns can change. Stay informed about updates from NANPA and the FCC to ensure your application remains compliant and functional.

Test Across Carriers: Verify your application works correctly with different carriers serving the 940 area (AT&T, Verizon, T-Mobile).

Implement Rate Limiting: Protect your application and avoid TCPA violations by implementing appropriate rate limiting for outbound calls and SMS.

Respect Time Zones: Area code 940 is in Central Time (CT). Schedule calls and messages appropriately to avoid contacting users outside 8 AM – 9 PM CT.

Advanced Implementation Considerations:

• Number Portability: Users can move numbers between carriers. Don't rely solely on area code for location-based routing.
• VoIP Integration: Ensure your VoIP implementation properly handles 10-digit dialing and E.164 formatting.
• Emergency Services: Verify that 911 calls are properly routed and include accurate location information.
• 988 Handling: Ensure your application doesn't block or misroute 988 Suicide & Crisis Lifeline calls.

Frequently Asked Questions About Area Code 940

What cities are covered by area code 940?

Area code 940 covers 79 cities across 23 counties in north-central Texas, including major cities like Denton (165,998 population), Wichita Falls (102,372), Gainesville, Mineral Wells (15,100), and Vernon. The coverage area serves approximately 2.6 million residents and extends through Denton County, Wichita County, Cooke County, Palo Pinto County, and 19 other counties.

Where is area code 940 located?

Area code 940 is located in Texas, specifically in the north-central region of the state. It covers the Denton and Wichita Falls metropolitan areas and surrounding communities across 23 counties and 79 cities.

What time zone is area code 940?

Area code 940 is in the Central Time zone (CT), which is GMT-6 (or GMT-5 during Daylight Saving Time). All locations within the 940 area code observe Central Time, which is critical for developers scheduling calls and ensuring TCPA compliance with time-of-day restrictions (8 AM – 9 PM local time).

When did 10-digit dialing become mandatory for area code 940?

10-digit dialing became mandatory on October 24, 2021 for all calls within area code 940. This change was implemented by the FCC to support the 988 Suicide & Crisis Lifeline, which launched nationwide on July 16, 2022. A permissive dialing period ran from April 24 to October 24, 2021, allowing both 7-digit and 10-digit dialing before the mandate took effect.

When was area code 940 created?

Area code 940 was created on July 7, 1997 as a split from area code 817. The split was necessary due to increasing demand for phone numbers driven by the proliferation of cell phones, fax machines, and internet connections in the rapidly growing north-central Texas region.

Is area code 940 getting an overlay?

No, area code 940 is not currently in jeopardy and will not run out of numbers. There is no relief planning or overlay currently underway. Area code 940 remains the only area code for its geographic coverage area with no immediate plans for changes.

What is the 988 Suicide & Crisis Lifeline and how does it affect area code 940?

The 988 Suicide & Crisis Lifeline is a nationwide three-digit number for mental health crisis support that became operational on July 16, 2022. To prevent confusion with existing phone numbers starting with 988, the FCC mandated 10-digit dialing for area code 940 and over 80 other area codes. Callers must now dial the area code + 7-digit number for all calls, even local ones.

What are the latitude and longitude coordinates for area code 940?

The approximate center of area code 940 is located at latitude 33.21484 and longitude -97.13307. However, the area code covers a wide geographic expanse across north-central Texas, so developers building location-based services should account for this range when implementing geographic routing or mapping features.

How do I validate phone numbers for area code 940?

Validate area code 940 numbers using the 1+10D format (1 + area code + 7-digit number). Use libraries like Google's libphonenumber (Python: phonenumbers, JavaScript: libphonenumber-js) for robust validation. Your validation should accept formats like +1-940-XXX-XXXX, 1-940-XXX-XXXX, (940) XXX-XXXX, or 940-XXX-XXXX, then normalize to E.164 format (+19407XXXXXX) for storage. See code examples above for Python and JavaScript implementations.

What is NANPA and how does it relate to area code 940?

NANPA (North American Numbering Plan Administration) manages area codes and numbering resources across the North American Numbering Plan. NANPA allocates area codes like 940, assigns number blocks (prefixes) to telecommunications providers, and oversees number pooling where numbers are assigned in blocks smaller than the traditional 10,000. The FCC provides regulatory oversight for NANPA's operations.

What major universities are located in area code 940?

Area code 940 includes several major educational institutions in Denton County, most notably the University of North Texas (enrollment ~40,000+) and Texas Woman's University (enrollment ~15,000+) in Denton. These universities contribute significantly to the region's education-focused economy and bring a large student population to the area code's coverage zone. Additionally, Midwestern State University serves the Wichita Falls area.

Do I need to dial 1 before the area code for local calls in area code 940?

While 10-digit dialing (area code + 7-digit number) is mandatory for local calls within area code 940, the "1" prefix before the area code is typically required for long-distance calls and depends on your carrier. Most modern telephony systems and mobile carriers handle this automatically, but developers should implement the 1+10D format (1 + area code + 7-digit number) for maximum compatibility across different carriers and systems.

What are STIR/SHAKEN requirements for area code 940?

STIR/SHAKEN is FCC-mandated caller ID authentication technology required for voice service providers since June 30, 2021. If you're building telephony applications that originate calls to area code 940 numbers, work with STIR/SHAKEN-compliant providers, properly configure your Service Provider Code (SPC) token, and never spoof caller ID information. All providers must file certifications in the Robocall Mitigation Database.

What TCPA rules apply to calling area code 940 numbers?

The Telephone Consumer Protection Act (TCPA) requires prior express written consent for autodialed calls and texts to wireless numbers. New rules effective January 27, 2025 require one-to-one consent for each seller, and April 11, 2025 rules mandate processing opt-outs within 10 business days. Respect Central Time zone restrictions (no calls before 8 AM or after 9 PM), honor the Do Not Call Registry, and maintain detailed consent documentation to avoid penalties of $500–$1,500 per violation.

Next Steps for Area Code 940 Telephony Integration

Now that you understand area code 940 telecommunications, enhance your implementation with these production-ready features:

Implement 10-Digit Validation – Use libphonenumber library (Python: phonenumbers, JavaScript: libphonenumber-js) to validate 940 area code numbers in 1+10D format and normalize to E.164 standard (+19407XXXXXX). See code examples above.

Add Geographic Routing – Use the 23-county coverage data and latitude/longitude coordinates (33.21484, -97.13307) to implement location-aware call routing for emergency services or local business directories.

Configure 988 Handling – Ensure your telephony application properly routes 988 calls to the Suicide & Crisis Lifeline and doesn't block or misroute these critical calls.

Implement STIR/SHAKEN Compliance – Work with STIR/SHAKEN-compliant telephony providers, configure SPC tokens properly, and file required certifications in the Robocall Mitigation Database.

Enable TCPA Compliance – Implement consent tracking, provide clear opt-out mechanisms (STOP for SMS), process opt-outs within 10 business days, and respect Central Time zone restrictions (8 AM – 9 PM).

Monitor NANPA Updates – Subscribe to NANPA notifications and FCC announcements to stay informed about potential future changes to area code 940 or new overlay implementations.

Handle Legacy 7-Digit Input – Implement graceful error handling for users who attempt to dial 7-digit numbers, providing clear feedback about the 10-digit dialing requirement with specific error messages.

Test Multi-Carrier Compatibility – Verify your application works correctly across different carriers serving the 940 area (AT&T, Verizon, T-Mobile), including proper handling of the 1+10D format.

Implement Number Pooling Logic – If your application requires large volumes of phone numbers, understand NANPA's number pooling guidelines for acquiring numbers in blocks smaller than 10,000.

Set Up Monitoring and Logging – Implement comprehensive logging for all telephony operations, consent tracking, opt-outs, and compliance activities to support audits and troubleshooting.

Additional Resources:

• NANPA Official Website – Area code information and numbering plan updates
• FCC 988 Suicide & Crisis Lifeline – Official information about 988 implementation
• FCC Ten-Digit Dialing Guide – Consumer guide to 10-digit dialing requirements
• FCC STIR/SHAKEN Call Authentication – Caller ID authentication requirements and compliance guide
• FCC TCPA Consumer Guide – Telephone Consumer Protection Act regulations
• Area Code 940 Statistics – Current coverage data and statistics
• Google libphonenumber – Phone number parsing, formatting, and validation library
• Robocall Mitigation Database – FCC database for STIR/SHAKEN compliance certification

Conclusion: A Developer's Perspective on Area Code 940

This guide has provided you with a comprehensive overview of area code 940, going beyond basic information to explore its geographic, regulatory, and historical context. By understanding the mandatory 10-digit dialing requirements, implementing proper phone number validation with libraries like libphonenumber, ensuring STIR/SHAKEN caller ID authentication compliance, and adhering to TCPA regulations, you can develop robust and compliant telephony applications that serve the needs of users in north-central Texas.

Key Takeaways:

• Always normalize phone numbers to E.164 format (+19407XXXXXX) for storage
• Use established libraries rather than custom regex for validation
• Implement STIR/SHAKEN and TCPA compliance from day one, not as an afterthought
• Respect Central Time zone restrictions and user consent preferences
• Stay informed about regulatory updates from NANPA and the FCC

Always validate user input, handle dialing variations gracefully, implement comprehensive error handling, and stay updated on the latest telecommunications regulations to ensure your applications remain compliant and functional. With proper implementation of the techniques and best practices covered in this guide, you'll build telephony applications that are reliable, compliant, and user-friendly for the 2.6+ million residents served by area code 940.