Castlerock — managed IT and business connectivity provider in South Africa
Castlerock is a managed IT services provider running from Westlake in Cape Town, with further offices in Johannesburg and Dublin. Its stated job is to simplify IT complexity for growth-minded businesses, and the service list runs from a 24/7 helpdesk and cybersecurity through Microsoft cloud services, business continuity and disaster recovery, managed private cloud hosting, procurement and licensing, and governance, risk and compliance. VoIP call solutions sit inside that managed stack rather than being sold as a standalone product.
Key facts
| Who they are | A managed IT services provider that partners with growth-minded businesses to simplify the complexity of IT, operating from Cape Town, Johannesburg and Dublin |
| Voice services | VoIP call solutions, delivered as part of the managed service rather than as a standalone product. If you want a phone system on its own, a dedicated voice provider is the better starting point |
| Also offers | 24/7 IT support and helpdesk, cybersecurity covering endpoint protection, firewall, email security and vulnerability assessment, Microsoft cloud services, business continuity and disaster recovery, IT consulting and strategy, procurement and licensing, managed private cloud hosting, and governance, risk and compliance |
| Head office | G1, 1 Westlake Drive, Westlake, Cape Town, 7945 |
| Coverage | South Africa from two offices, plus a Dublin presence. Castlerock is a managed service provider rather than a network operator, so connectivity is arranged on your behalf rather than built |
| Domain | The company now trades on castlerock.co. The older castlerock.co.za address redirects there, so a bookmark or an old invoice pointing at the .co.za domain still resolves |
| ICASA licence | No ICASA reference is published. A managed service provider reselling voice does not necessarily hold its own ECS licence; ask which licensed operator carries the calls if that matters to your procurement |
| Pricing | Quote-based. Nothing is published, which is normal for managed IT, where the monthly figure depends on user count, device count and which services are in scope |
| Trading since | Not published on the site |
| Listed In | Fibre Internet Providers |
An IT department, with the phones attached
Castlerock is not an ISP and does not pretend to be. What it sells is the function a growing company usually cannot staff properly: a 24/7 helpdesk, patching and endpoint protection, Microsoft 365 administration, backup that has actually been tested, and someone accountable when a laptop is stolen on a Friday afternoon. VoIP sits inside that, which is the right way round for a business whose phones are one more thing IT has to keep working, and the wrong way round for a contact centre shopping specifically for a voice platform. The Dublin office alongside Cape Town and Johannesburg is worth noting if you have staff or a parent company in Europe, since the same provider can cover both. Nothing is priced publicly, so the useful comparison is scope rather than rate: get two quotes that list the same devices, users and response times. Compare connectivity options in the fibre provider directory.
Who Castlerock is a fit for
- Companies that want an outsourced IT department rather than a phone system alone
- Cape Town and Johannesburg businesses needing a 24/7 helpdesk
- Groups with staff or a parent company in Ireland or the UK
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Compare phone systems →Commonly asked questions
Is Castlerock an internet provider?
No. It is a managed IT services provider. Connectivity and VoIP are arranged as part of a managed service, but the company does not build or run its own network.
Where does Castlerock operate?
From offices in Cape Town, Johannesburg and Dublin. Its Cape Town base is at G1, 1 Westlake Drive in Westlake.
Has the website address changed?
Yes. Castlerock now trades on castlerock.co, and the older castlerock.co.za address redirects there, so old links and invoices still resolve to the right place.
Does Castlerock sell phone systems?
VoIP call solutions are part of the managed service list. If a phone system is the main thing you are buying, compare dedicated voice providers as well, since a managed IT provider prices voice as one line in a wider contract.
What does managed IT cost?
Pricing is not published. Managed IT is quoted on user count, device count and scope, so compare two quotes that cover the same devices, the same services and the same response times rather than comparing headline rates.
What is included in the cybersecurity service?
Endpoint protection, firewall management, email security and vulnerability assessment are listed, alongside governance, risk and compliance as a separate service line.
This listing is maintained by WhichVoIP, an independent South African telecoms comparison service running since 2019. Details are verified against the provider’s public website and were last reviewed on 29 July 2026.