What Email Systems Do US Dental Practices Actually Use? We Checked All of Them.

The National Breakdown

Every US dental practice email in our database, classified by the mail system its domain actually routes to (July 2026):

Shares of 39,817 unique practice inboxes. Remaining 0.1%: domains with no resolving MX record. Bars scaled to the largest segment.

Finding 1: More Than 1 in 4 Practices Runs on Consumer Email

27.6% of US dental practices use a consumer email address, a plain @gmail.com (19.3%) or Yahoo, AOL, iCloud, or an ISP address (8.3%), as the practice's actual working inbox. Not a forgotten legacy address: the inbox printed on the website and answered by the front desk.

This is the single most consequential number in the study for anyone building a dental outreach list, because the big B2B databases structurally exclude these practices. Hunter's policy is to never return webmail addresses, and platforms built on professional web footprints rarely capture them. If your data source filters out consumer email, it silently deletes over a quarter of the US dental market before your first send. (This is also why general B2B databases run thin on dentists.)

Finding 2: Google Handles 44.3% of Dental Practice Email

On paid business email, it is a dead heat: 25% of practices run Google Workspace against 24.7% on Microsoft 365. Add the plain-Gmail practices and Google's mail servers receive 44.3% of dental practice email, nearly double Microsoft's share.

For senders this is mostly good news, because Google's filtering is the most predictable to work with: forgiving of newer domains at low volume, transparent via Postmaster Tools, and governed by published bulk-sender rules (full authentication and a spam rate under 0.3%). The Microsoft quarter of the market is where sender reputation builds slowest, and it deserves its own warmup plan.

The split also varies more by state than most senders expect: Minnesota is 40.3% Microsoft 365 while Washington, D.C. is 37.0% Google Workspace, and California practices use plain Gmail (23.7%) at nearly twice the rate of Minnesota. The full state table is in the gated section below.

Finding 3: 1 in 11 Practices Sits Behind a Security Gateway

8.8% of practices route email through a dedicated security gateway, and Proofpoint owns this segment: 6.9% of all US dental practices, 78% of the gateway segment, with Barracuda and Mimecast splitting most of the rest. These are the hardest inboxes to reach with a new sending domain, and they are exactly the segment that silently destroys campaign statistics when treated like the rest of the list.

The geography is dramatic. Nevada (21.8%), South Dakota (20.3%), and Arizona (18.5%) have four to five times the gateway share of New York (3.9%). A sequence that performs beautifully into Manhattan can bounce off Las Vegas, and without infrastructure data you would blame the copy.

Finding 4: Dental-Specific Vendors Are Visible in the MX Records

Two names in the MX data are unique to this industry: EnGuard, a HIPAA-compliant email provider (307 practices), and ProSites, a dental website and marketing company that also hosts practice email (285 practices). Together with dental-IT-focused MSP filters, they are a reminder that dentistry has its own infrastructure vendors that generic deliverability guides have never heard of, and their filtering behavior is undocumented anywhere. We will be tracking these segments across future refreshes.

The Full State-by-State Breakdown

Provider mix for all 50 states plus D.C., from 51 state-level segments with at least 50 analyzed inboxes each, plus the sending playbook for each infrastructure segment:

Methodology

In July 2026 we took every verified practice email in our database of 67,989 US dental practices, 39,817 unique inboxes after deduplication, and classified each domain's live DNS MX records (26,502 unique custom domains resolved). Consumer webmail domains were classified directly; custom domains were bucketed by their lowest-priority MX host: Google Workspace (aspmx.l.google.com), Microsoft 365 (*.mail.protection.outlook.com), named security gateways (Proofpoint, Barracuda, Mimecast, and other filtering services), and hosting providers. State shares are computed only where a state has 50+ analyzable inboxes, which all 51 jurisdictions cleared. Details on how the underlying practice database is built and verified are on our methodology page.

Citing this study: please attribute to DentistEmailList.com and link this page. The headline figures are the 27.6% consumer-email share, the 8.8% gateway share, and the 44.3% Google-routed share, as of July 2026.

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