How many area codes does Maryland have?

Maryland has 5 active geographic area codes in the North American Numbering Plan: 240, 301, 410, 443, 667. Each code serves a distinct region or acts as an overlay for a high-demand metro area.

What is the oldest area code in Maryland?

The oldest area code in Maryland is 301, assigned in 1947. It serves Rockville and the Western Maryland region. 301 is one of the original 86 area codes created when the North American Numbering Plan was first established.

Can I get a Maryland phone number from anywhere?

Yes. DialPhone virtual phone numbers are not tied to a physical location. You can get a Maryland area code number and use it from any device — desktop, mobile, or browser — anywhere with an internet connection. This makes Maryland numbers ideal for remote teams, distributed businesses, and sales teams targeting Maryland customers.

How much does a Maryland area code number cost?

DialPhone plans start at $24 per user per month on the Core plan. Every plan includes your choice of Maryland area code number, unlimited US and Canada calling, business SMS, AI call captions, and a free 14-day trial — no credit card required. See the DialPhone pricing page for current tier details.

Can I port my existing Maryland number to DialPhone?

Yes. DialPhone supports free number porting from any major US or Canadian carrier, including existing Maryland area code numbers. Porting typically completes in 2 to 5 business days with zero service interruption. See the complete number porting guide for step-by-step instructions.

What time zones are used in Maryland?

Maryland area codes span the ET time zone. When scheduling calls with Maryland customers, verify the specific area code's time zone to avoid calling outside business hours.

Area Codes in Maryland — Local Business Phone Numbers

Quick answer

Maryland has 5 active geographic area codes covering Baltimore, Rockville. The most-recognized codes are 301, 410, 443, serving Baltimore and the Greater Baltimore region.

Total codes: 5
Top metro: Baltimore
Time zone: ET
Largest code: 410 (Baltimore)

By Darshan M

Growth Operations Lead at DialPhone · Verified against NANPA data

Area codes in Maryland

Maryland is served by 5 active geographic area codes in the North American Numbering Plan. These codes were assigned between 1947 and 2012 as population and call demand grew across the state.

Code	Primary City	Region	Established	Overlay Codes	Population
240	Rockville	Western Maryland	1997	301	1,500,000
301	Rockville	Western Maryland	1947	240	1,500,000
410	Baltimore	Greater Baltimore	1991	443, 667	2,800,000
443	Baltimore	Greater Baltimore	1997	410, 667	2,800,000
667	Baltimore	Greater Baltimore	2012	410, 443	2,800,000

Time zones in Maryland

All area codes in Maryland fall in the ET time zone.

ET — area codes: 240, 301, 410, 443, 667

Top metros and their area codes

Below are the primary cities in Maryland and the area codes that serve each metro. Cities with multiple codes share geography due to overlay assignments added as demand grew.

Baltimore — 410 , 443 , 667
Rockville — 240 , 301

Why get a local Maryland number?

A Maryland area code number gives your business three core advantages:

Local trust signal. Customers in Maryland recognize local area codes as their own. A familiar caller ID builds immediate credibility for service businesses, sales teams, and patient communication.
Higher answer rate. Calls from a local area code are answered far more often than toll-free or out-of-area numbers — industry data puts the lift at 20–40%. That difference matters most for outbound sales, appointment confirmations, and service callbacks.
Targeted marketing. Advertising a local Maryland number on print, radio, digital, and outdoor channels converts better than a national 800 number for audiences who prefer doing business locally.

How to get a Maryland area code number with DialPhone

Setting up a Maryland business number takes under 10 minutes:

Sign up for a DialPhone plan. Choose any plan starting at $24/user/month. Free 14-day trial, no credit card required.
Search available Maryland numbers. Filter the DialPhone number inventory by state, area code, city, or number pattern.
Choose your number and configure. Assign your new Maryland number to a user or team, configure call routing, voicemail, AI receptionist, and business SMS.
Port your existing number (optional). Already have a Maryland number? Free number porting completes in 2 to 5 business days with zero service interruption.