Bossar is a specialized eCommerce email marketing agency focused on email and SMS. With 5+ years of experience and a proven track record across 100+ stores, we focus exclusively on retention marketing that drives measurable results.
Most of the brands we work with are established eCommerce businesses, and the majority of our clients operate in the 6- to 8-figure revenue range. This focus allows us to craft strategies built for scale, helping growth-minded brands unlock the full potential of email and SMS. Our longest-standing client has been with us for over 4 years, proof that our strategies create growth that lasts.
As a full-service email marketing agency, our core offer is done-for-you email & SMS management, which covers every aspect of retention marketing, including:
Automated email & SMS flows tailored to your brand and customer journey
Campaign planning, execution, and optimization
Audience segmentation and advanced personalization
Custom design + conversion-driven copywriting
Deliverability monitoring and inbox placement
A/B testing and performance optimization
Detailed reporting and actionable insights
If your store is under $50K/month in sales or you’re not ready for ongoing monthly management, we also offer one-time flow setups and custom projects designed to match your tech stack and business needs. Whether you need a dedicated Klaviyo email marketing agency or support with another ESP, our team builds flows and campaigns tailored to your system.
With Bossar, you’re not hiring a generic provider, you’re partnering with a retention-focused email marketing agency that lives and breathes email & SMS, turning them into your most profitable growth channels.
Want to identify missed revenue opportunities in your retention marketing? Visit our website and apply for a free audit here: bossar.agency/free-audit (no obligations) to get actionable insights tailored to your store.
Min project size
$5,000+
Hourly rate
Undisclosed
Employees
10 - 49
Locations
Warszawa, Poland
Year founded
Founded 2021
1 Locations
Warszawa , Poland
No have been added yet...
Pricing Snapshot
Min. project size
$5,000+
Avg. hourly rate
Undisclosed
Rating for cost
5
/5
What Clients Have Said
Bossar offers competitive pricing and delivers excellent value, with clients noting strong results such as over $7.6M in email revenue and $407,000 monthly growth. They are praised for their budget-friendly services and effective communication, making them a reliable choice for various project sizes.
Bossar has generated substantial revenue for clients, with notable increases in email and SMS revenue, thanks to their strategic marketing efforts and innovative approaches.
No Significant Areas for Improvement
Clients have not identified significant areas for improvement, indicating a high level of satisfaction with Bossar's services and performance.
Proficiency in Email and SMS Marketing
Bossar excels in email and SMS marketing, delivering significant revenue growth and impressive engagement metrics for clients through strategic optimization and effective campaign management.
Responsive and Collaborative Team
Clients appreciate Bossar's responsiveness and the feeling of working with a team that acts as an extension of their own, providing data-driven insights and flexible solutions.
Strong Project Management Skills
Clients consistently praise Bossar's project management, highlighting their proactive approach, organization, timely deliveries, and clear communication, even during high-pressure periods.
"They're not just sending emails — they're building a high-converting system tailored to our brand."
Nov 24, 2025
Director, Cupids
Anonymous
Verified
Advertising & marketing
United States
11-50 Employees
Online Review
Verified
Bossar has revamped an e-commerce brand's email marketing strategy, executing Klaviyo campaigns, optimizing automated flows, conducting A/B tests, and coordinating with an SMS marketing tool for outreach.
Thanks to Bossar's efforts, the client has seen significant revenue growth, tripled click rates, and doubled placed order rates, all while reducing email volume. The team is proactive, organized, and timely, providing regular updates and delivering everything on time, even during peak seasons.
BACKGROUND
Introduce your business and what you do there.
I’m a director at Cupids, a fast-growing e-commerce brand.
OPPORTUNITY / CHALLENGE
What challenge were you trying to address with Bossar?
We needed help with our email marketing to drive more revenue through flow optimization, A/B testing, and highly effective Klaviyo campaigns.
SOLUTION
What was the scope of their involvement?
Bossar has handled a full email marketing revamp for our brand, including Klaviyo campaign strategy and execution, complete rebuild and optimization of our automated flows, and rigorous A/B testing of subject lines, email content, and send times. They’ve also integrated Postscript with Alia for better SMS coordination, built custom Black Friday flows and pop-ups, and continuously monitored performance to drive improvements in placed order rate, click rate, and revenue — all while reducing send volume.
What is the team composition?
We’ve worked with 2–5 teammates from Bossar.
How did you come to work with Bossar?
We found them through an online search and a referral. We chose them because their pricing fit our budget, and they knew what they were doing.
What is the status of this engagement?
We started working together in May 2025, and the engagement is ongoing.
RESULTS & FEEDBACK
What evidence can you share that demonstrates the impact of the engagement?
The results have been outstanding. Klaviyo-attributed revenue has grown from 13% to nearly 20%, adding over $407,000/month in extra revenue. Campaign click rates have tripled (from 0.13% to 0.4%), and campaign revenue has jumped to $1.63 million, even with reduced send volume. Our flows have seen placed order rates nearly double (0.27% to 0.52%) and generated over $2 million, up from just $664,000. All this has been achieved in just five months of work, with smarter segmentation, better creatives, and less volume — a huge win.
Additionally, our flow click rate has increased from 1.57% to 1.9%, indicating stronger engagement with automated emails. Our campaign revenue has risen to $1.63 million from $967,000, even with lower send volume (almost 7 million fewer emails sent), proving better targeting and messaging. Our flow revenue has tripled to over $2 million, all while keeping send volume efficient and proportional to store revenue.
How did Bossar perform from a project management standpoint?
Bossar’s project management has been excellent. They’re proactive, organized, and consistently hit deadlines without us needing to chase them. Communication is clear and timely — they regularly update us on A/B test results, flow performance, and upcoming campaign plans. Everything from strategy execution to creative updates is delivered on time, even during high-pressure periods like Black Friday. It truly feels like working with an in-house team that has full ownership.
What did you find most impressive about them?
What impresses us most about working with Bossar is how deeply they understand both the technical and creative sides of email marketing. They’re not just sending emails — they’re building a high-converting system tailored to our brand. Their ability to drive major revenue growth while reducing email volume is something we haven’t seen before. On top of that, their team is responsive, data-driven, and genuinely feels like an extension of our internal team.
Are there any areas they could improve?
Honestly, our experience with Bossar has been overwhelmingly positive.
RATINGS
5.0
Quality
5.0
Service & Deliverables
Schedule
5.0
On time / deadlines
Cost
5.0
Value / within estimates
Willing to Refer
5.0
NPS
Email Marketing for Pet Products Company
Email MarketingSMS Marketing
$50,000 to $199,999
Jan. 2023 - Oct. 2025
5.0
Quality
5.0
Schedule
5.0
Cost
5.0
Willing to Refer
5.0
"We are satisfied with the service."
Nov 24, 2025
CEO, TherapetMD
Firas Balaffou
Verified
eCommerce
Sheridan, Wyoming
11-50 Employees
Online Review
Verified
Bossar provided email and SMS marketing services for a pet products company. The team developed marketing strategies, created content, designed marketing materials, and utilized Klaviyo as their primary tool.
Thanks to Bossar's efforts, the client generated over $1.5 million in email revenue and over $500,000 in SMS revenue. The team communicated clearly, responded to the client's needs, and had a fast turnaround. They were flexible and open to testing new ideas.
The client submitted this review online.
BACKGROUND
Please describe your company and position.
I am the CEO of TherapetMD
Describe what your company does in a single sentence.
Sell pet product
OPPORTUNITY / CHALLENGE
What specific goals or objectives did you hire Bossar to accomplish?
Email marketing
Sms marketing
SOLUTION
How did you find Bossar?
Clutch Site
Why did you select Bossar over others?
High ratings
Pricing fit our budget
Good value for cost
Company values aligned
How many teammates from Bossar were assigned to this project?
2-5 Employees
Describe the scope of work in detail. Please include a summary of key deliverables.
The Bossar agency helped us build a strong email and SMS marketing foundation that drove great results. They handled strategy, copy, design and Klaviyo with clear communication and fast turnaround.
RESULTS & FEEDBACK
What were the measurable outcomes from the project that demonstrate progress or success?
-Over $1.5M in email revenue added
- Over $500k extra revenue driven from SMS
- 3X email list growth (opt-in forms jumped from 9% to 30%+)
Describe their project management. Did they deliver items on time? How did they respond to your needs?
Clear communication and fast turnaround.
What was your primary form of communication with Bossar?
Virtual Meeting
What did you find most impressive or unique about this company?
They are flexible and open to testing new things.
Are there any areas for improvement or something Bossar could have done differently?
Can’t think of any at this time, we are satisfied with the service.
RATINGS
5.0
Quality
5.0
Service & Deliverables
Schedule
5.0
On time / deadlines
Cost
5.0
Value / within estimates
Willing to Refer
5.0
NPS
Email & SMS Marketing for Print-On-Demand Company
Email MarketingSMS Marketing
Confidential
Jan. 2022 - Ongoing
4.5
Quality
4.5
Schedule
5.0
Cost
5.0
Willing to Refer
4.5
"They're open to new ideas and quick in implementation."
Sep 24, 2024
CMO, Povney LLC
Yevhenii Ahapov
eCommerce
Gillette, Wyoming
11-50 Employees
Online Review
Maillibr has set up and now maintains a print-on-demand company's email and SMS marketing. The team has set up automations, such as abandoned checkout reminders, and established a process for regular campaigns.
Maillibr's work generates 15%–20% of the client's store revenue. The team is quick to respond, and their communication is straightforward via email and messaging apps. Moreover, the client is open to new ideas and has a fast turnaround time. Overall, the client is satisfied with Maillibr's work.
The client submitted this review online.
BACKGROUND
Please describe your company and position.
I am the CMO of Povney LLC
Describe what your company does in a single sentence.
We run print on demand stores around the globe
OPPORTUNITY / CHALLENGE
What specific goals or objectives did you hire Maillibr to accomplish?
Setup and maintain our email marketing
SOLUTION
How did you find Maillibr?
Referral
Why did you select Maillibr over others?
Close to my geographic location
Pricing fit our budget
How many teammates from Maillibr were assigned to this project?
2-5 Employees
Describe the scope of work in detail. Please include a summary of key deliverables.
We need to set up all the necessary automations, such as the welcome series and abandoned checkout reminders. Additionally, we need to establish a process for regular campaigns.
RESULTS & FEEDBACK
What were the measurable outcomes from the project that demonstrate progress or success?
15-20% of the store's revenue is generated by the team through Email and SMS
Describe their project management. Did they deliver items on time? How did they respond to your needs?
The team always responds quickly in communication. Communication is mostly straightforward.
What was your primary form of communication with Maillibr?
Email or Messaging App
What did you find most impressive or unique about this company?
They're open to new ideas and quick in implementation.
Are there any areas for improvement or something Maillibr could have done differently?
No idea :)
RATINGS
4.5
Quality
4.5
Service & Deliverables
Schedule
5.0
On time / deadlines
Cost
5.0
Value / within estimates
Willing to Refer
4.5
NPS
Email Marketing for Branding Agency
Email MarketingSMS Marketing
$50,000 to $199,999
Jan. 2021 - July 2024
5.0
Quality
5.0
Schedule
5.0
Cost
5.0
Willing to Refer
5.0
"They are adaptive to new initiatives, proactively propose ideas, and engage in strategies that continuously improve."
Jul 22, 2024
CEO, Creatunity
Andrew Payne
Verified
Advertising & marketing
Dallas, Texas
11-50 Employees
Online Review
Verified
Maillibr provided email marketing services for a branding agency. The team customized the lifecycle of the email flows, collected zero-party data, managed opt-in data, and deanonymized data via Retention.com.
Maillibr's work significantly increased the client's email revenue by over $7.6 million and new email subscribers by over 600,000. The team also improved the client's marketing strategies and A/B testing. The team delivered on time and was responsive, adaptative, and proactive during the engagement.
The client submitted this review online.
BACKGROUND
Please describe your company and position.
I am the CEO of Creatunity
Describe what your company does in a single sentence.
We create innovative, high-growth brands that make life better.
OPPORTUNITY / CHALLENGE
What specific goals or objectives did you hire Maillibr to accomplish?
Growth
Marketing
SOLUTION
How did you find Maillibr?
Referral
Why did you select Maillibr over others?
High ratings
Good value for cost
Referred to me
Company values aligned
How many teammates from Maillibr were assigned to this project?
2-5 Employees
Describe the scope of work in detail. Please include a summary of key deliverables.
With 3 years of partnership delivering more than $7.6M in email revenue, more than 600k new email subscribers added through the following scope:
Custom lifecycle email flows
Zero-party data collection
Opt-in management
Deanonymizing strategy via retention.com
Advanced list segmentation
Email campaigns calendar
RESULTS & FEEDBACK
What were the measurable outcomes from the project that demonstrate progress or success?
$7.6M+ in email revenue generated and 600k+ new email subscribers added, along with clear strategy improvements, A/B testing and planning with our team.
Describe their project management. Did they deliver items on time? How did they respond to your needs?
Quick communication, always consistent and on time with deliverables.
What was your primary form of communication with Maillibr?
Email or Messaging App
What did you find most impressive or unique about this company?
They are adaptive to new initiatives, proactively propose ideas, and engage in strategies that continuously improve.
Are there any areas for improvement or something Maillibr could have done differently?
At this time there are no areas I can suggest for improvement.
RATINGS
5.0
Quality
5.0
Service & Deliverables
Schedule
5.0
On time / deadlines
Cost
5.0
Value / within estimates
Willing to Refer
5.0
NPS
E-commerce Development for an Online Shop
E-Commerce Development
Less than $10,000
Dec. 2018 - Jan. 2019
5.0
Quality
5.0
Schedule
5.0
Cost
5.0
Willing to Refer
5.0
"Their communication was very good and they always delivered punctually."
Feb 27, 2019
Employee, Online Marketing Firm
Anonymous
Verified
Advertising & marketing
Nordhorn, Germany
1-10 Employees
Online Review
Verified
Bossar built and implemented a configurator and did e-commerce development for an online store. They provided expertise in the WooCommerce plugin.
They delivered a functional online store ahead of the deadline. Expect a team that works hard to meet specifications and can accommodate changes in implementation requirements.
The client submitted this review online.
BACKGROUND
Please describe your company and your position there.
We are an online marketing agency.
OPPORTUNITY / CHALLENGE
For what projects/services did your company hire Bossar?
We hired them to develop an online store.
What were your goals for this project?
We wanted a well-designed online store.
SOLUTION
How did you select this vendor?
We found them on the internet and chose them for their expertise in WooCommerce.
Describe the project and the services they provided in detail.
They built and implemented a configurator for us and supported the implementation of the online store.
What was the team composition?
We worked with three people on their end.
RESULTS & FEEDBACK
Can you share any information that demonstrates the impact that this project has had on your business?
They delivered much faster than we expected.
How was project management arranged and how effective was it?
Their communication was very good and they always delivered punctually.
What did you find most impressive about this company?
They work conscientiously and properly and they’re also flexible in their implementation.
If you’re not seeing exactly what you need here, send this company a custom message.
You can talk about your project needs, price, and timeline to get started on your project.
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