317 Area Code: Indianapolis, IN | Location & Time Zone

The 317 area code is one of Indiana’s most recognizable telephone area codes, serving the heart of the state including Indianapolis and its surrounding metropolitan area. As the primary area code for Indiana’s capital and largest city, 317 has been connecting residents, businesses, and visitors since 1947. Whether you’re planning to call Indianapolis, relocating to central Indiana, or simply curious about this historic area code, this comprehensive guide covers everything you need to know about the 317 area code, including its geographic coverage, time zone information, history, and dialing instructions.

What is the 317 Area Code?

The 317 area code is a telephone area code serving Indianapolis and the central Indiana region. Established on January 1, 1947, as part of the original North American Numbering Plan (NANP), 317 was initially assigned to cover the entire state of Indiana. Over the decades, as Indiana’s population grew and telephone demand increased, the coverage area was reduced through several splits, leaving 317 to serve primarily the Indianapolis metropolitan area and surrounding counties.

Today, the 317 area code covers Marion County (home to Indianapolis) and portions of the surrounding “doughnut counties” including Boone, Hamilton, Hancock, Hendricks, Johnson, Morgan, and Shelby counties. This region represents the economic, cultural, and governmental center of Indiana, housing major employers, educational institutions, healthcare facilities, and the state capitol.

317 Area Code Location & Coverage

Cities and Regions Covered

The 317 area code primarily serves the following cities and communities in central Indiana:

Marion County: Indianapolis (the state capital and largest city), Lawrence, Beech Grove, Southport, Speedway, and Cumberland. Indianapolis alone accounts for the vast majority of the population within the 317 area code, with approximately 880,000 residents as of 2024.

Surrounding Counties: Parts of Boone County (including Zionsville and portions of Whitestown), Hamilton County (Carmel, Fishers, Noblesville, and Westfield), Hancock County (Greenfield and portions of McCordsville), Hendricks County (Avon, Brownsburg, Danville, and Plainfield), Johnson County (Greenwood, Franklin, and Whiteland), Morgan County (Martinsville and Mooresville), and Shelby County (Shelbyville).

The 317 area code region represents Indiana’s most densely populated area, encompassing approximately 1.5 million residents across the greater Indianapolis metropolitan statistical area. This region is known for hosting the Indianapolis Motor Speedway, home of the famous Indianapolis 500 race, as well as being a major hub for healthcare, logistics, manufacturing, and technology industries.

Geographic Coverage Map

The 317 area code covers approximately 1,400 square miles in central Indiana, forming a roughly circular pattern around Indianapolis. The coverage area extends approximately 20-30 miles in all directions from downtown Indianapolis, though boundaries follow county lines and municipal borders rather than forming a perfect circle. To the north, the coverage reaches into southern Hamilton County; to the east, it extends into western Hancock County; to the south, it covers northern Johnson County; and to the west, it includes eastern Hendricks and Morgan counties.

Time Zone Information

The entire 317 area code region observes Eastern Time (ET). During standard time (typically November through March), the area operates on Eastern Standard Time (EST), which is UTC-5. During Daylight Saving Time (typically March through November), the region observes Eastern Daylight Time (EDT), which is UTC-4. Indiana’s relationship with time zones has an interesting history—until 2006, most of Indiana did not observe Daylight Saving Time, but the entire state now follows the DST schedule, making it easier for businesses and residents to coordinate with other states. If you need to compare times across different timezones, planning your calls to the 317 area code becomes much simpler when you account for the Eastern Time Zone.

317 Area Code Details

History of the 317 Area Code

When Was 317 Created?

The 317 area code was created on January 1, 1947, as one of the original 86 area codes established under the North American Numbering Plan. At its inception, 317 covered the entire state of Indiana, making it one of the few area codes to serve an entire state. This was feasible in 1947 because telephone penetration was much lower, and the population of Indiana was significantly smaller than today.

The creation of area codes in 1947 revolutionized long-distance calling in North America by allowing direct-dial service without operator assistance. The number 317 followed the numbering pattern used at the time, where states or regions with lower populations received area codes with a middle digit of 1, making them quicker to dial on rotary phones.

Area Code Changes and Overlays

As Indiana’s population grew and telephone usage expanded, the 317 area code underwent several splits to accommodate demand:

1948: The northwestern portion of Indiana (Gary, Hammond, and the Calumet region) was split off to create the 219 area code, marking the first division of Indiana’s telephone numbering system.

1996: Northern Indiana received the 219 area code exclusively, while central Indiana retained 317, and a new 812 area code was assigned to southern Indiana.

October 1997: The most significant change occurred when the northern Indianapolis suburbs and surrounding areas were assigned the new 765 area code, while 317 was reserved for Indianapolis and its immediate metropolitan area. This split reduced the geographic coverage of 317 to approximately its current boundaries.

1999: The 930 area code was introduced as an overlay for the 812 region in southern Indiana, though this did not directly affect 317.

Currently, the 317 area code does not have an overlay, meaning it is the only area code serving its geographic region. However, as phone numbers become increasingly scarce due to the proliferation of mobile devices, fax lines, and internet-based services, telecommunications authorities have discussed the possibility of introducing an overlay area code in the future. When this occurs, callers within the 317 region may need to dial 10 digits for all calls, even local ones.

How to Call the 317 Area Code

Dialing Within the Area Code

For local calls within the 317 area code region, callers can typically dial just the seven-digit phone number (XXX-XXXX) without needing to include the area code. However, best practices recommend using the full 10-digit format (317-XXX-XXXX) to ensure call completion, especially as telephone systems modernize and prepare for potential overlay area codes. Mobile phone users should always dial the full 10-digit number, including the area code, regardless of whether the call is local.

Dialing From Other Area Codes

When calling a 317 number from outside the area code region but within the United States or Canada, you must dial 1 + 317 + the seven-digit phone number (1-317-XXX-XXXX). The “1” prefix indicates a long-distance call within the North American Numbering Plan. Most modern phone systems and mobile carriers handle this automatically, but it’s important to include the “1” prefix to ensure proper call routing.

International Dialing

For international callers reaching a 317 area code number, the format is: +1-317-XXX-XXXX. The “+1” represents the country code for the United States and Canada. Depending on your country, you may need to dial your international access code (such as 00 or 011) before the country code. For example, from the United Kingdom, you would dial 00-1-317-XXX-XXXX, while from many mobile networks worldwide, you can simply dial +1-317-XXX-XXXX.

Nearby Area Codes

The 317 area code is surrounded primarily by the 765 area code, which serves much of central and eastern Indiana outside the Indianapolis metro area. Understanding nearby area codes can be helpful when planning regional business operations or understanding calling patterns in central Indiana and surrounding states.

Population & Demographics

The 317 area code region serves approximately 1.5 million people, making it the most populous area code region in Indiana. Marion County alone, which contains Indianapolis, has a population of approximately 880,000 residents, while the surrounding counties within the 317 region add another 600,000-700,000 people.

Indianapolis and the 317 area code region have experienced steady population growth over the past two decades, driven by a diverse economy, affordable cost of living, and central geographic location. The region has a diverse demographic composition, with significant African American, Hispanic/Latino, and Asian communities contributing to the cultural and economic fabric of central Indiana.

Economically, the 317 area code region is a powerhouse for Indiana, serving as the state’s center for government, healthcare, education, logistics, advanced manufacturing, and technology. Major employers include Eli Lilly and Company (pharmaceuticals), Anthem/Elevance Health (health insurance), Indiana University Health, Salesforce, and numerous logistics and distribution companies taking advantage of Indianapolis’s central location and excellent transportation infrastructure. The region is also home to several universities and colleges, including Indiana University-Purdue University Indianapolis (IUPUI), Butler University, and the University of Indianapolis.

Frequently Asked Questions

What cities are in the 317 area code?

The 317 area code covers Indianapolis and its surrounding metropolitan area, including cities such as Carmel, Fishers, Noblesville, Westfield, Greenwood, Avon, Brownsburg, Plainfield, Franklin, Greenfield, Beech Grove, Lawrence, Speedway, Zionsville, and Martinsville. Marion County is entirely within the 317 area code, along with portions of Hamilton, Boone, Hendricks, Johnson, Hancock, Morgan, and Shelby counties.

Is 317 a toll-free area code?

No, 317 is not a toll-free area code. It is a standard geographic area code serving central Indiana. Toll-free area codes in North America include 800, 888, 877, 866, 855, 844, and 833. Calls to 317 numbers may incur long-distance charges depending on your calling plan and location.

What time zone is the 317 area code in?

The 317 area code is entirely within the Eastern Time Zone (ET). The region observes Eastern Standard Time (EST, UTC-5) during winter months and Eastern Daylight Time (EDT, UTC-4) during Daylight Saving Time, which typically runs from March through November. You can use a date calculator to help plan calls and meetings across different time zones.

Will the 317 area code get an overlay?

While there is no immediate overlay planned for the 317 area code, telecommunications authorities monitor number availability closely. As phone numbers become scarce due to increased mobile phone usage and internet-based phone services, an overlay may be introduced in the future. If an overlay is implemented, residents and businesses would keep their existing 317 numbers, but new numbers might be assigned a different area code, and 10-digit dialing would become mandatory for all calls.

How do I know if a call is from the 317 area code?

Incoming calls from the 317 area code will display “317” as the first three digits of the phone number on your caller ID. If you see a call from 317-XXX-XXXX, it indicates the call is originating from the Indianapolis metropolitan area in central Indiana. However, be aware that caller ID can be spoofed, so if you receive an unexpected call from a 317 number, verify the caller’s identity before sharing personal information.

Can I keep my 317 number if I move?

Yes, thanks to number portability regulations, you can typically keep your 317 phone number even if you move to a different area code region, as long as you maintain service with a provider that serves both areas or port your number to a new provider. Mobile phone numbers are especially portable. However, keeping an out-of-area number may result in long-distance charges for local calls in your new location, depending on your service plan.

Conclusion

The 317 area code has served Indianapolis and central Indiana for nearly eight decades, evolving from a statewide designation to the focused metropolitan identifier it is today. Understanding the 317 area code—its geographic coverage, time zone, history, and dialing instructions—is essential for anyone doing business in Indiana’s capital region, planning to relocate to Indianapolis, or simply staying connected with friends and family in central Indiana. As Indianapolis continues to grow and thrive as a Midwestern hub for business, healthcare, education, and culture, the 317 area code remains an enduring symbol of the city’s identity and an essential part of its telecommunications infrastructure.