However, based on market reputation, customer feedback, and product range, here are the leading and most reputable CCTV camera sellers in Bangladesh, categorized for clarity:

Top-Tier Established Companies (For Large Projects & Premium Brands)
These are the market leaders known for quality products, professional installation, and strong after-sales service.

Security Gadget BD: Arguably the most well-known and trusted name. They are for Hikvision and offer a wide range of other brands like Uniview, Dahua, CP Plus, etc. They cater to everything from small shops to massive government projects.

Why they’re top: Official warranty, certified engineers, large inventory, reliable support.

Genius Advanced Communications Ltd.: Another giant in the security industry. They are a major distributor for Dahua Technology and also carry other leading brands. They have a very strong nationwide presence.

Why they’re good: Extensive dealer network, good technical support, comprehensive solutions.

Sena Technologies Ltd.: A highly reputable company offering solutions from Honeywell, Bosch, and other international brands. Known for high-end, professional commercial and industrial systems.

Why they’re good: Premium brand portfolio, focus on enterprise solutions, quality engineering.

Excellent Sellers for SMEs, Homes & Shops (Value & Service)
These companies offer great balance between price, service, and product variety.

Interlink Technologies Ltd.: A strong player distributing brands like CP Plus, Vantage, and others. They are known for competitive pricing and good customer service for small to medium businesses.

Star Tech & Rahimafrooz (Retail Partners): While not system integrators, Star Tech’s physical and online stores, along with Rahimafrooz’s “My Rahi” outlets, are trusted retailers for branded CCTV kits (e.g., Hikvision, Dahua boxes). Good for ready-made packages for homes and small offices.

Key Online Marketplaces & Tech Retailers
For smaller, DIY setups or price comparison.

Pickaboo / Daraz / Ryans: These platforms host numerous official brand stores (like the Hikvision Official Store on Daraz) and reputable third-party sellers.

Advice: Always buy from the official brand store or a “Daraz Mall” seller with high ratings for authenticity. Be cautious of prices that seem too good to be true.

Important Considerations Before You Buy:
Brand: Hikvision and Dahua dominate the market due to price and features. CP Plus, Uniview, Honeywell, Bosch are also reputable. Ensure you are getting genuine products.

Your Need: Define the area to cover, required resolution (2MP, 4MP, 4K), night vision, weatherproofing (for outdoor), and whether you need features like audio, PTZ (Pan-Tilt-Zoom), or AI (person/vehicle detection).

After-Sales Service: This is crucial. The best seller provides installation support, warranty claims, and technical troubleshooting. Always ask about the warranty process.

Budget: Get quotations from at least 2-3 companies.

Final Recommendation:
For most people seeking a reliable setup for a business or home, starting your search with SS E-TECH or Genius Advanced (or their authorized dealers in your city) is a very safe bet.

For a large commercial/industrial project, consult with Sena Technologies and SS E-TECH for high-end solutions.

For a simple home/shop kit, check the official stores on Daraz/Pickaboo or visit Star Tech for a ready package.