For email marketing agencies, here’s a list:

• https://www.designrush.com/agency/email-marketing
• https://ecosystem.hubspot.com/marketplace/solutions/email-marketing
• https://clutch.co/agencies/email
• https://www.agencyspotter.com/search?industry_ids[]=22&industry_ids[]=32&industry_ids[]=47&location=&budget_min=0&budget_mid=infinity&optradio=project&q=&button=regular
• https://mailchimp.com/find-an-expert/?specialty=email_marketing&availability=1
• https://digitalagencynetwork.com/agencies/usa/email-marketing/
• https://topdigital.agency/agency/?fwp_expertise=community-management%2Cdata-analytics%2Cdigital-strategy%2Cemail-marketing
• https://www.shopify.com/partners/directory/services/marketing-and-sales/email-marketing
• https://www.sortlist.com/email-marketing
• https://upcity.com/lists#group_by=service&service=105
• https://www.awwwards.com/directory/?text=email marketing
• https://www.digitalagencies.gr/search_results?q=email+marketing

Advertising Agencies:

https://www.winmo.com/the-complete-list-of-stagwell-company-agencies/

All types of agencies:

• https://puddding.com/directory?country=usa