Best Email Marketing Agencies in 2026

Flowium is a retention agency founded in 2017 by Andriy Boychuk, who hosts its Email Einstein podcast. It builds Klaviyo flows and campaign calendars, then adds SMS, push, WhatsApp and direct mail as a brand grows, and sells standalone email audits and deliverability fixes. It says it has served more than 1,000 ecommerce brands, including Dr. Squatch, True Classic and Balsam Hill, holds a 4.9 Clutch rating across more than 20 reviews, and offers no long-term contracts.

InboxArmy handles email, SMS and push only, and works across more than 40 platforms including Salesforce Marketing Cloud, Braze, HubSpot and Klaviyo. Services cover audits, campaign management, automation, template coding, deliverability and platform migrations, with first campaigns typically live around week five. Since 2024 it has been led by Scott Cohen, the ANA's 2021 Email Marketer of the Year. Its logo wall includes Hilton, Sherwin-Williams, Expedia and Zappos.

Chronos Agency, started by Josh Chin in 2017, is a retention team of roughly 80 people across Singapore and Sydney serving about 60 ecommerce brands at a time. Email and SMS lead, with push, WhatsApp, RCS and direct mail added for lapsed customers. Each account gets a strategist, manager, copywriter and designer, plus a separate QA layer, and success is measured in customer lifetime value on a gross-profit basis. Clients include The Oodie and Truly Beauty.

Rejoiner is a software company first: since 2011 it has built its own retention platform for online retailers, covering cart and browse abandonment, win-back, replenishment, SMS and printed postcards, then wrapped managed services around it. A Strategy Partner tier starts from about $1,500 a month. It reports that AuthenTEAK grew email revenue 22% to more than $2M in 2024, and Humanscale and Barilla appear on its client list.

SeeResponse is a McLean, Virginia B2B growth agency founded in 2019, where clients work directly with a founder. Its Grow practice covers email, HubSpot administration and sales operations, and sits alongside ABM, outbound and content for mid-market SaaS companies. It reports a 36% lift in email revenue for Joovv, works with VWO and Knack, averages 4.9 across 37 Clutch reviews, and quotes month-to-month retainers of $2,500 to $7,500.

Belkins is a Denver agency focused on B2B outbound, running cold email, LinkedIn and calling together to book appointments. It is built for prospecting rather than ecommerce lifecycle email. It holds 234 Clutch reviews averaging 4.9, owns its deliverability tools, which cuts third-party software cost, and runs dedicated finance and consulting offers with named fintech clients and a $5,000 starter package.

Power Digital is a San Diego growth agency founded in 2012, with around 580 staff by a 2023 count, that runs email and SMS alongside paid media, SEO, content, CRO, affiliate and influencer work. Its Nova measurement platform focuses on incrementality and media mix modelling, which helps brands judge email's real contribution. Clients include Alice + Olivia, ASICS, Crocs and Cymbiotika.

Webprofits has run campaigns out of Sydney since 2006 and pairs paid search and paid social with customer lifecycle marketing on Klaviyo, where it is listed as a Platinum Master partner. It reports growing SharkNinja's Australian DTC channel from $5M to $52M and has worked with Aussie Broadband since 2016. Other clients include Logitech, LG and Levi's. In February 2026 it moved every team and client account into Claude Code.

Digital Media Team is a Manchester ecommerce agency whose Klaviyo and Mailchimp flows sit alongside paid social, Google Ads and Shopify builds. It is a Klaviyo Master Platinum Partner and won a 2023 Klaviyo Klicks Award for Best Win-Back or Sunset Flow. Clients include DeMellier London, MuscleFood and Missy Empire, and the agency reports more than £1 million in revenue for Rebellious Fashion. A £1,000 minimum is listed on Digital Agency Network.

1 At Bat Media is a Toronto agency that works only with online retailers, mostly Shopify brands with roughly $5 million to $50 million or more in revenue. Its model links Meta and Google acquisition with Klaviyo email and SMS retention, so the same team can see both sides of customer cost. It reports that Cutter & Buck grew DTC revenue 112% year over year with a larger share from email, and it holds a 5.0 rating from 16 Clutch reviews.

Avex is a New York Shopify Plus agency founded by John Surdakowski, who also co-founded the Shopify app Seguno. Retention marketing sits alongside its build, CRO and loyalty work, integrating with Attentive, Recharge, Rebuy and Ordergroove, so email and SMS are designed with the storefront. Its portfolio includes Hugo Boss, Kith, Calvin Klein and Khaite, and it cites more than $10B in combined client GMV.

SOUP is a senior-led Sydney agency founded by Katya Vakulenko in 2018 that runs Klaviyo or HubSpot email and CRM alongside Google Ads, paid social and SEO. It holds a 4.9 Clutch rating across 37 reviews, with reviewers often calling the team timely and proactive, and names LawConnect, RIPE Global, Roborock and Rebecca Vallance among its clients. A $50 to $99 hourly band and $1,000 minimum make it accessible to SMBs.