By Pete Devkota·Last reviewed ·Editorial · no paid placements
The best Klaviyo agencies in the USA, on our ranking, are Flowium (New York) for brands whose Klaviyo fundamentals are broken, UN/COMMON (Philadelphia), one of Klaviyo's two Americas Partners of the Year for 2026, for Shopify brands that want lifecycle marketing and store work from one agency, and Hustler Marketing (Jackson, Wyoming) for mid-market brands that want an account manager with a capped client load. Fuel Made fits Shopify Plus brands whose store is holding email back, InboxArmy (Grapevine, Texas) fits hands-on execution from a published $1,500 a month, and Darkroom and Stimulate publish their prices too.
Most "top Klaviyo agencies USA" lists are written by an agency that ranks itself first. This one is written by an agency too: we're Email Optimize, an Australian Klaviyo partner with West Coast-based team members, at #7, and the one entry here not based in the US. Our criteria for the US market: a Klaviyo partner directory listing you can check at connect.klaviyo.com, named US client work, US ecommerce specialism, the bench to cover Black Friday and the Q4 peak, and a clear best-fit profile. This list is deliberately different from our worldwide Klaviyo agency ranking: agencies that serve US brands from London or Singapore are covered there. Last reviewed October 2026.
About the author. Aeronautical engineer turned ecommerce email specialist. Pete founded Email Optimize in 2017 and is behind $250M+ in attributed email and SMS revenue across 800+ brands. Full profile →
Listings are tiers as shown in Klaviyo's partner directory in October 2026. Prices are only those the agency publishes on its own site, checked 10 October 2026; "Quote only" means it doesn't publish one.
Methodology
How we ranked the US Klaviyo agency market
Each agency is evaluated on six factors: (1) current Klaviyo Partner Directory tier, (2) named US clients with measurable revenue outcomes, (3) US ecommerce specialism vs platform-agnostic generalist work, (4) team depth and continuity, (5) Q4 / BFCM capacity, (6) clear best-fit profile. We do not accept paid placements, affiliate fees, or sponsored slots from any agency on this list.
This list covers agencies built around the US market. The one exception is us: we work with US brands from Adelaide, with West Coast-based team members, and our entry says plainly when a US-domestic agency is the better hire. Agencies that deliver to US brands from abroad, such as Underground Ecom (London) and Chronos Agency (Singapore), are on our worldwide Klaviyo agency list instead, so the two rankings answer different questions.
The list
The 10 best Klaviyo agencies for US brands, ranked
Best for US DTC wanting deep Klaviyo technical execution
Klaviyo Elite Master Partner (per Klaviyo partner directory, October 2026) · New York, NY
Flowium is a New York Klaviyo specialist, listed as Elite Master in Klaviyo's partner directory (October 2026). Retention specialist since 2017: email first, plus SMS, push, WhatsApp, RCS, Instagram DM automation and direct mail per their site. Strong fit for US brands whose program is underperforming due to broken fundamentals (flow architecture, segmentation, deliverability, attribution) rather than weak creative. Their case studies emphasize technical precision over creative storytelling.
Email-first retention agency, with SMS, push, WhatsApp, RCS and direct mail per their site
Elite Master, one of 47 worldwide in Klaviyo's partner directory (October 2026)
NYC HQ with East Coast US business hours coverage
Strong on deliverability, attribution, and flow architecture
Best for US Shopify brands that want lifecycle marketing and store work from one agency
Klaviyo Elite Master Partner (per Klaviyo partner directory, October 2026); Klaviyo Americas Partner of the Year 2026 · Philadelphia, PA
UN/COMMON is one of the two US-facing agencies Klaviyo singled out this year: at its K:Partners Awards, announced on 9 September 2026, Klaviyo named ECD Digital Strategy and UN/COMMON its Americas Partners of the Year. Klaviyo's directory lists UN/COMMON at Elite Master, and Shopify's partner directory lists it as a Platinum partner in Philadelphia. Per their site, the agency was founded in 2015, has 60+ people, and pairs email and SMS lifecycle work with Shopify Plus builds and CRO. Clients on their site include Rare Beauty, Liquid Death, Dermalogica and Ursa Major. Strongest fit for US Shopify brands that want lifecycle marketing and the store handled by one team.
Klaviyo Americas Partner of the Year 2026 (shared with ECD Digital Strategy)
Elite Master in Klaviyo's directory; Platinum partner in Shopify's
Founded 2015, 60+ people (per their site)
Clients: Rare Beauty, Liquid Death, Dermalogica, Ursa Major
Best for US mid-market DTC wanting high-touch account management
Klaviyo Elite Master Partner (per Klaviyo partner directory, October 2026) · Jackson, WY (per their site)
US-headquartered in Jackson, Wyoming, per their site. Deliberately low client-to-AM ratio (account managers handle a maximum of three stores, per their site), which produces strategic depth that's harder to deliver in higher-leverage models. Their client testimonials emphasize the embedded-team feel of the engagement. Strong fit for US mid-market DTC where the in-house team is small and the agency relationship needs to function like an extension of it.
Maximum of three stores per account manager (per their site)
Best for US Shopify Plus brands wanting integrated dev + email
Klaviyo Elite Master Partner (per Klaviyo partner directory, October 2026) + Shopify Plus partner (per Shopify's partner directory) · Colbert, WA
Washington State HQ. Elite Master in Klaviyo's partner directory, and listed in Shopify's partner directory as a Plus partner since 2011, a rare combination at credible depth. Strong fit for US brands whose Klaviyo program is held back by upstream Shopify Plus issues: checkout friction, integration gaps, customer data structure, or theme-level events not firing. Working with a separate Klaviyo agency and Shopify dev shop usually creates coordination overhead; Fuel Made internalizes both. Clients on their site include Beardbrand, Umbra, Figs and Briogeo.
Klaviyo Elite Master + Shopify Plus partner (per both directories, October 2026)
Full Shopify Plus development capability in-house
US West Coast HQ, Pacific time zone
Clients: Beardbrand, Umbra, Figs, Briogeo (per their site)
Texas-headquartered, with 120+ email marketing specialists and brands served since 2016, per their site. Full-service email and SMS agency with Klaviyo as one of 40+ platforms covered (also Salesforce Marketing Cloud, Mailchimp, HubSpot, Iterable). One of the few agencies that publishes a floor: "The minimum for our monthly managed services is $1,500 per month" (as of October 2026). Strong fit for US brands wanting execution at scale and willing to work with a platform-agnostic agency rather than a Klaviyo-exclusive specialist. They self-rank #1 on their own "top Klaviyo agencies" comparison, common practice in this market, including for us.
Klaviyo Silver Master Partner
Managed services from $1,500/month (published on their site)
120+ email marketing specialists, since 2016 (per their site)
Best for US Shopify DTC brands that want a retention-only team
Klaviyo Platinum Master Partner (per Klaviyo partner directory, October 2026)
Sticky Digital describes itself as a retention marketing agency focused on email, SMS, loyalty, subscription and tech stack work for Shopify brands, and Klaviyo's directory lists it at Platinum Master (October 2026). Its site doesn't state a head office, but the client list is US consumer DTC: PrettyLitter, Tubby Todd, MUD\WTR and r.e.m. beauty. The site also says it was "Voted #1 Retention Marketing Agency In North America 2023 + 2024" without naming who voted, so weigh that accordingly and ask for results instead. Strongest fit for US Shopify brands that want a team doing retention and nothing else.
Platinum Master tier in Klaviyo's partner directory
Email, SMS, loyalty and subscriptions for Shopify brands (per their site)
Best for US brands wanting senior operator depth, or one program across the US, UK and Australia
Klaviyo Partner · Adelaide, Australia (US delivery)
We are an Australian Klaviyo partner agency founded in 2017, and the one entry on this list not based in the US. We work with US brands from Adelaide, with West Coast-based team members, and we're honest about the model. The reason a US brand would choose us over a US-domestic agency is one of two specific things: (1) multi-market coverage, because you sell in Australia, New Zealand or the UK as well as the US and want one Klaviyo program across them; or (2) embedded senior operator depth: founder Pete Devkota served 22+ months as Head of Retention Marketing at Relaxium, an INC 5000 US supplement brand, inside the company rather than as an external consultant, where email and SMS added +$3M in incremental annual revenue. That depth of in-house operator perspective is uncommon for agency founders. $250M+ in attributed email and SMS revenue across 800+ ecommerce brands.
$250M+ attributed email and SMS revenue across 800+ brands
Pete Devkota: 9 years on Klaviyo, embedded Head of Retention at Relaxium (INC 5000)
Best for funded US DTC that wants retention run alongside paid media
Klaviyo Platinum Master Partner (per Klaviyo partner directory, October 2026) · New York, NY
Darkroom is a New York growth agency rather than an email specialist: paid media, performance creative, Amazon and AI search sit alongside retention marketing. Klaviyo's directory lists it at Platinum Master (October 2026), and it publishes prices: per its pricing page, retention marketing starts at $5,000 a month as of October 2026. Clients on its site include Everlane, Olipop, Nécessaire and Laundry Sauce. Strongest fit for funded US DTC brands where the email and SMS calendar needs to move in step with paid spend and creative testing. If you only need email, a specialist above will go deeper for less.
Platinum Master tier in Klaviyo's partner directory
Retention marketing from $5,000/month (published on their site)
Best for DTC brands that want a Klaviyo email and SMS team and a price before the first call
Klaviyo Gold Master Partner (per Klaviyo partner directory, October 2026) · St. Petersburg, FL (per their site)
Stimulate is a Florida agency that describes itself as a "Customer Retention Marketing Agency for DTC Brands", running email and SMS in Klaviyo. Klaviyo's directory lists it at Gold Master. It publishes a starting price: "Investment starts at $4k / month" on its homepage, as of October 2026. Its Nursing Queen case study reports email and SMS growing from 30.3% to 59.5% of total store revenue within 90 days. Founded in 2021 per its site, so it's younger than most agencies here. Strongest fit for DTC brands that want a Klaviyo email and SMS team and want to know the price before the first call.
Published pricing from $4,000/month (per their homepage)
Gold Master tier in Klaviyo's partner directory
Nursing Queen: email and SMS from 30.3% to 59.5% of revenue in 90 days (per their site)
Best for US DTC wanting Klaviyo email and SMS inside a full-funnel growth agency
Klaviyo Gold Master Partner (per Klaviyo partner directory, October 2026) · Los Angeles, CA
Los Angeles HQ, founded in 2011 per their site. A DTC growth agency that runs paid media, creative and analytics alongside Klaviyo email and SMS, with automation flows, segmentation and campaigns built as one program. On tier: their site describes them as a Klaviyo Master Elite partner, while Klaviyo's directory listed Gold Master when we checked in October 2026. Clients on their site include AppSumo, Atlas Coffee Club, MyIntent and Pixi Beauty. Strong fit for US DTC brands that want email and SMS coordinated with paid acquisition rather than run on their own.
Gold Master tier in Klaviyo's partner directory
LA HQ, US West Coast Pacific delivery
Email and SMS run alongside paid media and creative
Clients: AppSumo, Atlas Coffee Club, Pixi Beauty (per their site)
Practical decision
Who should hire which US Klaviyo agency
The US market has enough internal variation that the right agency choice differs meaningfully by brand profile, scale, and the specific lift needed.
US DTC with broken Klaviyo fundamentals (deliverability, attribution, flow architecture)
→ Flowium. Their entire methodology is built around fixing technical fundamentals.
US Shopify brand wanting lifecycle marketing and store work from one agency
→ UN/COMMON Agency, one of Klaviyo's Americas Partners of the Year for 2026.
US mid-market DTC wanting embedded-team feel
→ Hustler Marketing. Low client-to-AM ratio is the structural advantage.
US Shopify Plus with dev / integration blocking email lift
→ Fuel Made. Combined Klaviyo + Shopify Plus capability is rare.
US brand wanting hands-on execution, or on a platform other than Klaviyo
→ InboxArmy. Platform-agnostic, from $1,500 a month.
US Shopify DTC wanting a retention-only team
→ Sticky Digital.
US brand wanting embedded operator depth, or one program across the US, UK and Australia
→ Email Optimize. Pete's Relaxium operator background and multi-market delivery are our specific fit.
Funded US DTC wanting retention run with paid media
→ Darkroom, or Top Growth Marketing.
Brand that wants a published price before the first call
→ InboxArmy (from $1,500 a month), Stimulate (from $4,000) or Darkroom (retention from $5,000).
Enterprise DTC ($10M+) wanting an agency built for international scale
→ See Underground Ecom and Chronos Agency on our worldwide Klaviyo agency list.
By city
Klaviyo agencies by US city and region
Klaviyo work happens in the account and over video calls, so a US brand can hire from anywhere. If time zone or an in-person meeting matters, here's where the agencies on this list are based, per their own sites or Klaviyo and Shopify directory profiles (October 2026).
New York and the Northeast
Flowium (#1) is a New York Klaviyo specialist with East Coast business hours, and Darkroom (#8) is a New York growth agency with a retention team. UN/COMMON Agency (#2) is listed in Philadelphia in Shopify's partner directory and works mostly with Shopify brands. Flowium and UN/COMMON are listed at Elite Master in Klaviyo's directory, Darkroom at Platinum Master.
Los Angeles and Southern California
Top Growth Marketing (#10) is headquartered in Los Angeles, founded in 2011 and listed at Gold Master, with email and SMS run alongside paid media. If you're an LA brand weighing us, our Klaviyo agency for Los Angeles brands page covers how we work with Southern California DTC.
Texas
InboxArmy (#5) is in Grapevine, in the Dallas-Fort Worth area, with 120+ specialists per its site and a published $1,500-a-month minimum for managed services. It's platform-agnostic, so it suits Texas brands on Klaviyo and on other ESPs.
Florida and the South
Stimulate (#9) gives a St. Petersburg, Florida address on its site and publishes a starting price of $4,000 a month. In Nashville, Sweat Pants Agency, a fashion, beauty and lifestyle specialist, is on our worldwide Klaviyo agency list.
The West and Mountain West
Fuel Made (#4) is in Colbert, Washington, near Spokane, and pairs Klaviyo with Shopify Plus development. Hustler Marketing (#3) is in Jackson, Wyoming, and caps each account manager at three stores, per its site.
Serving the US from abroad
We (Email Optimize, #7) work with US brands from Adelaide, with West Coast-based team members and calls in US business hours. London's Underground Ecom and Singapore's Chronos Agency also deliver to US brands; both are on our worldwide Klaviyo agency list. An agency abroad makes the most sense when you sell in more than one market.
US rules and calendar
What a US Klaviyo agency should handle: CAN-SPAM, TCPA and Q4
Email. US marketing email runs under CAN-SPAM, an opt-out regime, plus state privacy laws such as California's CCPA. SMS is stricter: the TCPA, carrier rules under CTIA guidelines, and state laws with their own quiet hours. Ask any agency how it captures and stores SMS consent, and how opt-out keywords are handled.
Calendar. The US year is built around Black Friday, Cyber Monday and the Q4 holiday peak, with Memorial Day, the Fourth of July and Labor Day as smaller sale moments. Ask how the agency staffs November, when it locks the BFCM calendar, and how it protects deliverability when send volume jumps.
Klaviyo doesn't publish a count by country. Its become-a-partner page lists 6,500+ agency partners worldwide (October 2026), and the partner directory at connect.klaviyo.com lets you filter by location to see who is listed in the US right now. When we checked on 1 October 2026 the directory listed 47 Elite Master partners worldwide, its top tier.
At its K:Partners Awards, announced on 9 September 2026, Klaviyo named ECD Digital Strategy and UN/COMMON its Americas Partners of the Year, and IM Digital and Domaine its Global Partners of the Year. UN/COMMON is #2 on this list. An award is a useful signal, but still check who would work on your account and what they have done for brands like yours.
Tier confirms a baseline: active partner status, training depth, and demonstrated client outcomes. Elite Master is the top tier: Klaviyo's partner directory listed 47 Elite Master partners worldwide when we checked in October 2026. But a Silver or Gold partner with deep specialism in your category often outperforms an Elite Master partner that's spread thin across many platforms or verticals. Use tier as a baseline filter, not a final selection criterion.
Few agencies publish prices. As of October 2026: InboxArmy's managed services start at $1,500 a month, Stimulate says investment starts at $4,000 a month, Darkroom's retention marketing starts at $5,000 a month, and Duh Retention, a Postscript-focused agency, lists retainers of $5,000 to $12,000 a month with projects from $2,500. Most agencies on this list quote after a call. Ours: a free audit, projects at $3,000 to $15,000 USD, and retainers typically $3,000 to $12,000 USD a month, month-to-month. Klaviyo's own subscription is billed on top.
Usually only when there is specific expertise that US-domestic agencies don't offer. Common reasons: (1) cross-market coverage if your brand operates in AU/NZ or EU/UK too, (2) embedded senior operator depth that a particular international agency happens to bring, (3) significantly lower cost without quality trade-off. Time zone overhead, US holiday calendar coordination, and BFCM execution are the main things to verify the international agency handles well.
Required: (1) Show me your current Klaviyo Partner Directory listing, what tier are you actually at? (2) Show me 3 named US clients with revenue outcomes. (3) Walk me through how you would diagnose my current Klaviyo program in the first 30 days. (4) Who specifically would be on my account, what's their experience level, and how much of their week is on us? (5) How do you handle Q4 / BFCM capacity, what's your plan for the November-December peak? If the agency is vague on any of these, keep looking.
Because we work with US brands, with West Coast-based team members, and leaving ourselves off would hide a relevant option. We tell you exactly when we're the right fit (brands selling across the US, UK and Australia, or wanting the embedded operator depth from Pete's time as Head of Retention Marketing at Relaxium, an INC 5000 brand) and when a US-domestic agency is better. We don't take paid placements or affiliate fees from any agency listed.