425 Area Code: Bellevue, Redmond & Seattle's Eastside

The 425 area code is the telephone code of Seattle's Eastside — the string of cities that sits across Lake Washington from Seattle proper and runs north into Snohomish County. It rings across some of the most valuable suburban ground in the country: Bellevue's high-rise downtown, Redmond's software campuses, Kirkland's waterfront, and the Everett aerospace hub further north.

A phone number that begins with 425 signals the Puget Sound tech corridor rather than the city center — the Eastside, where Microsoft, Costco, T-Mobile and Nintendo of America all keep their headquarters.

Because 425 sits right beside Seattle's famous 206 code, it turns up in two very different searches: people who just received a 425 number and want to know exactly where it comes from, and people asking whether an unfamiliar 425 call is safe to answer.

This guide covers both — the Eastside and South Snohomish cities that make up the 425 region, how it split from 206 in 1997, the Pacific-Time detail that shapes its business day, what to watch for with spoofed calls, and how to activate a 425 virtual number for a business in minutes.

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The 425 area code is a telephone area code serving the eastern and northern suburbs of the Seattle metropolitan area in Washington State. It was put into service on April 27, 1997, when the original 206 code that had covered all of greater Seattle was split three ways — 206 kept the city itself, 253 took the south around Tacoma, and 425 took the Eastside and South Snohomish County.

It has covered that same territory as a single code ever since, anchored by Bellevue and Everett as its two largest cities.

Dialing Format and Time Zone

• Dialing format: (425) 555-0142
• International: +1 425-555-0142
• Time zone: Pacific Time (PT) — UTC−8 in winter, UTC−7 during Daylight Saving (mid-March to early November)
• Ten-digit dialing is standard across Washington, so the full (425) number is dialed on every call

Geographically, 425 wraps around the northern and eastern edges of the Seattle metro. It covers the Eastside cities of King County — the corridor east of Lake Washington — and continues north into South Snohomish County, taking in Everett and its neighbors. Between them the code stretches from the shores of Lake Washington up toward the Cascade foothills, covering dense downtowns, lakeside suburbs and the industrial waterfront of Everett.

Major Cities and Communities

• Bellevue — the largest Eastside city and the region's second downtown, a high-rise business core and home to T-Mobile US
• Redmond — the software capital of the Eastside, home to Microsoft's global headquarters and Nintendo of America
• Kirkland — a walkable waterfront city on Lake Washington's eastern shore
• Everett — the largest city in the northern half, an aerospace and port hub in South Snohomish County
• Renton — the southern gateway to the Eastside, with a long Boeing manufacturing history
• Issaquah, Sammamish & Bothell — fast-growing family suburbs in the Cascade foothills; Costco is headquartered in Issaquah
• Lynnwood, Edmonds, Mukilteo & Woodinville — northern and wine-country communities rounding out the region

Just across Lake Washington, Seattle proper keeps its original code — see the 206 area code for the city-center picture. The two form one continuous metro economy, and many companies hold numbers in both. To the south, 253 covers Tacoma and South King County, while further out the 360 area code rings the rural stretches of western Washington beyond the metro.

The entire 425 region observes Pacific Time (PT) — UTC−8 during Pacific Standard Time in the fall and winter, and UTC−7 during Pacific Daylight Time from mid-March through early November. This puts the Eastside on the same clock as Seattle, Portland, San Francisco and the rest of the West Coast, three hours behind New York and eight behind London.

For businesses, the practical detail is that a 425 number sits at the western edge of the US business day. A 9 a.m. start in Bellevue is noon in New York, which makes the late afternoon on the Eastside the natural window for reaching the East Coast, and the morning ideal for Asia-Pacific markets across the Pacific.

A 425 number with flexible cloud call routing makes covering those spread-out hours simple, letting a company forward calls and set schedules around a steady Pacific-Time presence.

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For its first fifty years, greater Seattle shared a single area code. When the North American Numbering Plan assigned codes in 1947, 206 covered all of western Washington, and even after 360 was carved off for the rural areas in 1995, 206 still blanketed the entire Seattle metro. The Eastside tech boom of the mid-1990s changed that: Microsoft, McCaw Cellular and a wave of software firms drove demand for new numbers faster than 206 could supply them.

• 1947 — 206 assigned to all of western Washington as one of the original NANP codes
• 1995 — 360 split from 206, taking the rural fringes of western Washington
• April 27, 1997 — 206 split three ways: 206 kept Seattle, 253 took Tacoma and the south, and 425 was created for the Eastside and South Snohomish County
• November 16, 1997 — the permissive-dialing period ended and 425 became mandatory across the Eastside

The split gave the Eastside its own identity on the phone for the first time. Where a 206 number had once meant anywhere in greater Seattle, a 425 number now specifically meant the suburbs east and north of the city — the fast-growing side of the lake where the technology industry was concentrating. That distinction has held for nearly thirty years, and 425 has never itself been split or overlaid since, though that is now set to change.

An area code rarely carries as much corporate weight as 425 does. The Eastside is one of the densest concentrations of technology headquarters in the United States, and a 425 number reads as authentically local across all of it — from the software campuses of Redmond to the high-rise offices of downtown Bellevue and the aerospace floor in Everett.

The Eastside Technology Corridor

Redmond is home to Microsoft's sprawling global headquarters and to Nintendo of America, while Bellevue hosts T-Mobile US and a fast-growing downtown that now rivals Seattle's for office space. Costco runs its worldwide operations from nearby Issaquah, and cloud, gaming and startup firms fill the corridor in between. Together they make the Eastside a technology center in its own right, not merely a suburb of Seattle.

Aerospace, Ports and Foothills

The northern half of 425 carries a different economy. Everett is home to one of the largest aircraft-assembly buildings in the world and a deep-water port, and Renton to the south has decades of aerospace manufacturing history of its own. Around them, the foothill suburbs of Sammamish, Issaquah and Bothell add biotech, retail and one of the highest-income residential bases in the Pacific Northwest.

Modern cloud phone providers let a business activate a 425 number in minutes — no Bellevue or Redmond office, no hardware, and no long-term contract. Search available 425 numbers, complete a short verification, and route the line to any device anywhere in the world. Because the code is instantly recognizable as Seattle's Eastside, the number reads as authentically local across the whole tech corridor, even for a team working remotely from elsewhere.

A 425 number suits anyone who wants to feel rooted in the Eastside: software and cloud startups near the Redmond and Bellevue campuses, professional-services firms serving the metro, aerospace and logistics suppliers around Everett and Renton, and remote teams targeting the Puget Sound market from out of state. Setting up a dedicated business phone number on 425 takes only a few steps.

MeraTalk provides 425 numbers as part of its cloud telephony platform — lines activate in minutes, route to any device, and pair with voicemail, call recording, an auto-attendant and CRM integration from one dashboard. To get started, search available numbers at meratalk.com.

For nearly thirty years, 425 has been a single, standalone code — no split and no second code layered on top. That is now changing. Washington adopted the 564 area code as a statewide overlay to add numbering capacity as older codes run low, and after launching over the 360 region it is slated to expand across the rest of the state, 425 included.

An overlay means a new code covering the same geography rather than a split, so no existing 425 number ever has to change.

• 425 keeps its number — an overlay adds capacity on top of the existing code, it does not reassign anyone
• New lines in the region may be issued on the 564 overlay code once it reaches the Eastside
• Ten-digit dialing is already the norm in Washington, so day-to-day dialing does not change when the overlay arrives

For a business choosing a number today, the takeaway is simple: a 425 line still reads unmistakably as Seattle's Eastside, and the coming overlay does not dilute that. It adds room for the region to keep growing while every current 425 number stays exactly as it is — a durable local signal across Bellevue, Redmond, Everett and everything between them.

425 is a legitimate, well-established Washington code, but like any area code its numbers can be spoofed. Caller-ID spoofing lets a fraudster make any number — including a 425 prefix — appear on a screen, so a resident sees what looks like a nearby Bellevue or Everett business, bank or agency calling.

The prefix itself proves nothing: a genuine 425 call and a spoofed one look identical, and scammers deliberately choose a familiar local code because people are more likely to answer it.

• Fake bank or payment alerts — a voicemail or text about a 'suspicious transaction' pushing you to call back or tap a link
• Tech-support imposters — callers claiming to be from a well-known Eastside software company about a 'problem' with your device
• Utility and delivery threats — messages that your power will be cut or a package held unless you pay a small fee immediately

The reliable defense is to hang up and call back through a number you find independently — on a bill, an official website or a saved contact. No genuine bank, utility or government agency demands gift cards or wire transfers over the phone, and a local-looking 425 caller ID is never proof of who is really on the line.

If a call turns out to be fraudulent, Washington residents can file a consumer complaint with the state Attorney General's office, and any pressure to act immediately should be treated as a warning sign in itself. For more, see file a consumer complaint.

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