Every firm that runs UltraTax CS has to decide where the software lives, and the choice affects busy-season performance, your IT workload, and how well you can defend your written information security plan (WISP) to a regulator. This guide compares four UltraTax CS hosting options: Rightworks, Thomson Reuters’ own Virtual Office CS, Azure Virtual Desktop, and an on-premises server.
The short answer
UltraTax CS hosting means choosing the machine your firm’s copy of UltraTax runs on: a hosted platform such as Rightworks or Virtual Office CS, Microsoft’s Azure Virtual Desktop inside a Microsoft tenant your firm owns, or a server in your office. Hosted platforms fit a small office with few users and modest data, at a monthly price per seat; one Thomson Reuters price list puts Virtual Office CS at $147 per user. AVD fits a growing firm that wants control, pays Microsoft for what it actually runs, and can switch IT partners without moving a single server. A new office server is the hardest case to make: one building carries all the risk, and hardware delivery stretched past 40 weeks in the 2026 memory crunch. Whichever host you pick, the FTC Safeguards Rule stays with your firm, so the choice belongs in your WISP.
Start with what Thomson Reuters requires, because every option has to meet it. UltraTax CS runs on Windows 11 or Windows Server 2016 through 2025, and network installations need a full Windows Server installation. The same page says Thomson Reuters does not support network-attached storage devices as file servers unless they allow a Windows host control, and it advises against wireless networks for CS Professional Suite applications. Those system requirements rule out many improvised setups before you compare prices.
Per the same page, workstations need at least 4 GB of RAM, with 8 GB or more recommended. Thomson Reuters adds that workstation requirements drop significantly when you run the application in the Virtual Office CS or SaaS environment. That detail matters for firms with older laptops, since hosting moves the heavy lifting off the desk.
Rightworks is the option that asks the least of your team. Thomson Reuters lists it as a hosting partner and says it offers three service levels called Hosted Essentials, Hosted Plus, and Hosted Advanced. The company states that more than 10,000 accounting firms use it.
The partnership dates to 2023, when CPA Practice Advisor reported that Right Networks and Thomson Reuters had agreed to offer cloud hosting of UltraTax CS and related software to U.S. firms. The same report describes the service as taking the burden of managing applications, security, and IT off the firm. That support is the real product. When a return fails to transmit on April 14, you call one vendor that already knows your application.
The tradeoff is control. You work inside the provider’s environment, on the provider’s maintenance schedule, and you pay a recurring fee per user. For a firm of five to thirty people without a full-time IT person, that trade usually favors Rightworks.
Azure Virtual Desktop (AVD) provides Microsoft-hosted infrastructure that you can configure yourself (with your own Azure team) or through an IT partner. Microsoft’s pricing page explains that Azure infrastructure is required to deploy Azure Virtual Desktop, and that eligible Microsoft licenses grant access to Windows session hosts. If your staff already holds qualifying Microsoft 365 licenses, you may owe no separate access fee.
Windows Server session hosts add a licensing step. Windows Server Remote Desktop Services is available at no extra cost if you hold an eligible RDS Client Access License with active Software Assurance.
UltraTax CS officially supports Windows Server, so an AVD session host runs it on a platform Thomson Reuters stands behind. You pay for compute, storage, and networking, and those costs track usage, so a firm that scales servers up in March and down in June can better control costs than it could with fixed hardware.
The catch is that Microsoft supplies only the platform. Your team or your IT partner must build the host pool, install UltraTax on a supported server, and fix problems when a state module misbehaves. Thomson Reuters publishes Terminal Server best practices for exactly this kind of deployment, and your IT partner should read them before the first install. AVD suits firms with an IT provider they trust or an internal technologist who is comfortable in Azure.
An on-premises server keeps data on-site and puts every decision in your hands, along with every risk. A CPA office is not a datacenter. It runs on one power feed and one internet line, so a local outage, a fire or a flood stops the whole firm. Microsoft runs Azure in datacenters grouped into availability zones, each with its own power, cooling and networking, so a failure in one leaves the others running. Replacing hardware is slower and dearer than it was, too: the 2026 memory shortage has driven up server prices and pushed lead times for larger memory orders past 40 weeks.
Thomson Reuters spells out the technical conditions. LAN and server installations should not sit on the server’s C: drive, and each person using the suite should have a local administrator account. You also need port 443 open so that CS Professional Suite applications can reach the authentication servers. Read the installation considerations before you buy hardware.
Then count the work that never ends. You patch the operating system, replace failed drives, test backups, and keep the machine running during tax season. Remote staff feel it most. Every session runs through your office internet line and a VPN with remote desktop gateway you build and defend, and a slow line means slow returns. Insurers watch the same door: cyber insurer Coalition reported a 123% jump in claims tied to attacks on remote desktop access, so a server holding tax data that staff reach from home is a question your underwriter will ask, and it can show up in your premium.
Hosted platforms are built to be sticky. The harder a platform is to leave, the longer a firm stays, so the exit is complicated and expensive by design. Ask how you leave before you ask how you join.
The exit
What leaving a typical hosted (non-AVD) cloud looks like:
The difference is who owns the environment. A hosted platform owns the servers your firm works on and hands back the data. With AVD, the servers sit in a Azure tenant, so changing IT partners changes who's the partner of record for that tenant and and the servers stay where they are.
Moving UltraTax to someone else’s servers does not move your legal obligations. The FTC Safeguards Rule (16 CFR Part 314) treats tax preparers as financial institutions, and the IRS Office of Professional Responsibility confirms the rule covers accounting firms that prepare income tax returns and must maintain a written information security plan. The IRS covers the same ground in Publication 4557, and Publication 5708 provides a template for the plan itself.
Your host counts as a service provider under the rule, and paragraph 314.4(f) gives you three duties toward it: choose a host capable of safeguarding client data, require those safeguards in the contract, and assess the host on a schedule. A provider such as Rightworks can give you documentation to attach to the plan. When PK Tech runs your AVD environment, PK Tech supplies the configuration documentation for your plan. With your own server, every line of the plan describes your own work. Whatever you choose, ask for written answers about encryption, backup frequency, and breach notification before you sign or migrate.
Match the option to the person who will answer the phone when something breaks.
| RightworksManaged hosting | Virtual Office CSThomson Reuters' cloud | Azure Virtual DesktopManaged by PK Tech, hosted by Microsoft | Your own serverOn-premises | |
|---|---|---|---|---|
| Who supports it | Rightworks | Thomson Reuters | PK Tech | In-house IT or an outside provider |
| How it's priced | Per user |
Per user |
Pay for what you use |
Hardware + upkeep |
| Trade-off | Little admin accessLimited customizationCostlier as you grow | Little admin accessLimited customizationCostlier as you grow | Fully customizableStorage scalesFair, usage-based rate | Patching, repairs and backups are all yoursRemote staff limited by the office internet |
| If you leave | ⚑ Locked inLeaving means downtime and a migration project | ⚑ Locked inLeaving means downtime and a migration project | ✓ Not locked inYour Azure tenant moves to any Microsoft partner | Your hardware, your data |
| Best fit | Few users, little data | CS Suite only, little data | Growing firms that want control | Hard to recommend for a new setup |
If you already work with an IT provider who knows Azure, or you employ someone who does, AVD deserves a serious quote. Ask for a monthly estimate covering compute, storage, backup, and licensing at your peak user count, then compare it to Rightworks pricing at the same headcount. Make the provider show the math.
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PK Tech has worked with CPA firms as a managed IT service provider for more than 16 years, and holds AICPA SOC 2 Type II attestation, verified by an independent audit of its security and privacy controls. Bring your headcount and the name of whoever fixes your IT today.
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