| Price from | — | $13/mo |
| Free plan | — | Yes |
| Free trial | — | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| iOS | — | Yes |
| Android | — | Yes |
| API | Yes | Yes |
| Plans published | 2 | 5 |
| Spec score · Transactional Email Software | 7.5 (#34) | 9.2 (#2) |
| Spec score · Transactional email services | 7.0 (#40) | 8.8 (#8) |
| Company history | Mithi's company timeline lists ClrStream among its products in 2018 and identifies ClrStream 2.5 in 2024. | Mailchimp was founded in Atlanta in 2001 by Ben Chestnut and Dan Kurzius. |
| Integrations | ClrStream integrates with directory services, Vaultastic, ERP, CRM, core banking, and other business applications through APIs and open protocols. | Mailchimp advertises more than 300 integrations, including Shopify, WooCommerce, Canva, Zapier, Salesforce, WordPress, Stripe and QuickBooks Online. |
| Security | The maker describes spam, virus, and malware protection with a 7-layer security architecture and real-time threat mitigation. | Mailchimp says its SOC 2 reports cover security, availability and processing integrity, and it maintains ISO 27001 certification and a VPAT. |
| Support | The maker offers access to a help desk, solution architects, and scheduled product demonstrations. | Official feature pages state 24/7 service and support, with onboarding specialists and customer-success services for paid customers. |
| What it does | ClrStream is an enterprise email notification platform for automating high-volume customer and stakeholder communications. | Mailchimp is an email and marketing-automation platform for growing businesses, combining email, social, landing pages, advertising and AI recommendations. |
