Insights

Direct Mail Scale Open Letter Marketing specializes in high-volume direct mail with in-house production and API support, suggesting a strong fit for mid-market to enterprise clients looking to scale direct mail programs efficiently.

Real Estate Lean Owned by a seasoned real estate investor, the company leverages direct mail for its own projects, indicating credibility with real estate and property management verticals and potential cross-sell to similar asset-heavy industries.

Tech Enabled A diversified tech stack including Microsoft Advertising, HubSpot, CRM/analytics tools, and a direct mail API implies readiness for integration into marketing automation workflows, appealing to teams prioritizing automation.

Growth Partnerships Recent partnership with Invelo as a direct mail vendor signals openness to channel partnerships and affiliate-style collaborations, presenting a path for co-marketing and referral-driven opportunities.

Midmarket Revenue With 11-50 employees and revenue in the low to mid single digits, there is opportunity to position Open Letter Marketing as a scalable, cost-effective direct mail partner for growing SMBs seeking reliable production and service.

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Open Letter Marketing Tech Stack

Open Letter Marketing uses 8 technology products and services including Microsoft Advertising, HubSpot Analytics, Linkedin Insight Tag, and more. Explore Open Letter Marketing's tech stack below.

Microsoft Advertising
Advertising
HubSpot Analytics
Analytics
Linkedin Insight Tag
Analytics
Microsoft Clarity
Analytics
WordPress
Content Management System
WooCommerce
E-commerce
Drift
Live Chat
Sendinblue
Marketing Automation

Media & News

Invelo, Inc. partners with Open Letter Marketing, Inc..
Invelo has partnered with Open Letter Marketing as its direct mail vendor.
Apr 28, 2022 | inveloapp.com

Open Letter Marketing's Email Address Formats

Open Letter Marketing uses at least 1 email format:

Open Letter Marketing Email Formats	Example	Percentage
First@openlettermarketing.com	John@openlettermarketing.com	100%

Frequently Asked Questions

What is Open Letter Marketing's official website and social media links?

Open Letter Marketing's official website is openlettermarketing.com and has social profiles on LinkedIn.

How much revenue does Open Letter Marketing generate?

As of October 2026, Open Letter Marketing's annual revenue is estimated to be $1M - $10M.

What is Open Letter Marketing's NAICS code?

Open Letter Marketing's NAICS code is 5418 - Advertising, Public Relations, and Related Services.

How many employees does Open Letter Marketing have currently?

As of October 2026, Open Letter Marketing has approximately 14 employees across 2 continents, including North America and Asia. Key team members include Production And Process Manager: K. B. and Prepress Lead: L. A. L. Explore Open Letter Marketing's employee directory with LeadIQ.

What industry does Open Letter Marketing belong to?

Open Letter Marketing operates in the Marketing Services industry.

What technology does Open Letter Marketing use?

Open Letter Marketing's tech stack includes Microsoft Advertising, HubSpot Analytics, Linkedin Insight Tag, Microsoft Clarity, WordPress, WooCommerce, Drift and Sendinblue.

What is Open Letter Marketing's email format?

Open Letter Marketing's email format typically follows the pattern of First@openlettermarketing.com. Find more Open Letter Marketing email formats with LeadIQ.

When was Open Letter Marketing founded?

Open Letter Marketing was founded in 2016.

Open Letter Marketing

Q: How many employees does Open Letter Marketing have currently?

Open Letter Marketing has approximately 14 employees.

Q: What technology does Open Letter Marketing use?

Open Letter Marketing's tech stack includes Auxilia, Shopify, Bootstrap, Font Awesome, Swiper.

Q: What is Open Letter Marketing's NAICS code?

Open Letter Marketing's NAICS code is 5418 (Advertising, Public Relations, and Related Services).

Marketing ServicesMassachusetts, United States11-50 Employees

Open Letter Marketing provides direct mail services at scale, emphasizing speed, reliability, and consistency. From campaign setup to in-house production and delivery, the company manages the end-to-end process to enable clients to send and repeat mailings efficiently. It offers a direct mail API alongside a hands-on service model, supporting both automated workflows and fully managed campaigns.
Based in Lawrence, Massachusetts, the company serves a diverse set of businesses that rely on direct mail as part of their outreach. It is owned and operated by Justin Silverio, a real estate investor, and operates with a small-to-mid-sized team. A 2022 partnership with Invelo, Inc. positioned Open Letter Marketing as a direct mail vendor for that company.