The short answer
Many US finance teams still run accounting or ERP software installed on their own servers, such as long-established desktop and server products (Sage 100 is a familiar example). The alternative is cloud ERP, either software as a service (SaaS) from the vendor or the same kind of software hosted for you in a cloud data center.
Neither is automatically cheaper or safer. On-premise suits organizations with stable needs, capable IT support and a reason to keep systems in-house. Cloud suits organizations that want remote access, fewer servers to manage and regular updates. A hosted option sits in between.
Three deployment models
| Model | What it means | Who runs the servers | Who applies upgrades |
|---|---|---|---|
| On-premise | Software installed on servers you own, in your office or data center | You or your IT provider | You or your IT provider |
| Hosted (private cloud) | Your licensed or open-source ERP runs on cloud servers dedicated to you | Your hosting or IT provider | Usually your provider, on a schedule you agree |
| SaaS | You subscribe to the vendor's multi-tenant service | The vendor | The vendor, on its schedule |
Open-source ERP such as ERPNext (ERPNext documentation) can be installed on your own servers or run on cloud servers, so the same software can be deployed on-premise or hosted.
The financials face-off
Cost profile. On-premise usually means upfront licenses, servers and implementation (capital spending), plus annual maintenance and IT support. SaaS usually means a per-user subscription (operating spending) that includes hosting and upgrades. Compare over five years and include internal staff time, backups, security tools, server replacement, integrations and training. Subscription prices tend to rise with users and modules.
Control and customization. On-premise and hosted systems generally allow deeper customization and direct database access for reporting. SaaS limits customization to what the vendor supports, which protects upgrades but can constrain unusual processes.
Upgrades. On-premise systems often fall behind because upgrades are disruptive and customizations break. SaaS keeps you current automatically, but you must test and adapt to changes you did not choose.
Security. On-premise security is entirely your responsibility: patching, backups, access, physical security. In the cloud, responsibility is shared. Cloud providers publish shared responsibility models, and the customer remains responsible for user access and data even with SaaS, and remains accountable for its information overall (NIST publishes cloud security guidance at its Computer Security Resource Center). A well-run SaaS provider may offer stronger infrastructure security than a small server room, but weak passwords and broad permissions are still your problem.
Access and continuity. Cloud ERP is available anywhere with an internet connection, which helps remote staff, multiple locations and business continuity. On-premise systems need secure remote access (VPN or remote desktop) and a recovery plan if the server fails.
Integration. Cloud ERPs usually offer modern APIs for banking, payroll, e-commerce and CRM connections. Older on-premise products may rely on file exports or add-ons. Check the specific integrations you need.
Reporting and month-end. Both can support multi-entity consolidation, multi-currency and multi-state sales and use tax reporting, but capabilities vary widely by product and edition. Test your actual month-end reports during evaluation.
US data location and record-keeping
For tax purposes, the IRS expects you to keep records that support the income, deductions and credits on your returns, and retention periods depend on the type of record and the tax at issue; state tax agencies, payroll rules and industry regulations can add their own periods (IRS). The IRS also expects electronic records to be readable and available on request. Confirm retention periods and the format of archived records with your accountant before you migrate or decommission a system.
For personal information, there is no single federal rule on where data may be stored. The FTC expects organizations to keep their data security promises and to protect the information they hold, and state privacy laws generally require contracts with service providers that limit how they use the data (FTC). Health data brings HIPAA business associate agreements, and some government and defense contracts require US-based hosting or specific authorizations (for example FedRAMP or CMMC).
Ask any cloud vendor which region hosts your data, where backups and support staff are located, and whether you can export all your data. A US region supports residency preferences but does not settle every question on its own. This is general information, not legal or tax advice.
When to move to the cloud
Moving is worth considering when:
- Your server or ERP version is approaching end of support.
- Staff work remotely or across several locations.
- Upgrades have been postponed for years because of customizations.
- You struggle to patch, back up and secure the server reliably.
- You need integrations your current product cannot provide.
Staying on-premise may be reasonable when your system is stable and supported, your IT support is capable, integrations are few, and you have specific control or connectivity requirements.
Decision checklist
- Five-year cost compared for on-premise, hosted and SaaS, including internal time
- End-of-support dates for our current software and server known
- Required integrations listed and confirmed for each option
- Month-end and tax reports tested with our own data
- Data location, backup location and support access confirmed in writing
- Record-keeping requirements reviewed with our accountant
- Customizations we truly need identified
- Full data export available if we leave
- Migration plan and parallel-run period agreed
Limitations
This comparison is general. Product capabilities, licensing and hosting options change often, so verify current terms with each vendor. Migration itself carries cost and risk; plan data cleansing, testing and a parallel month-end before switching.
Next step
Our ERP implementation service compares options against your requirements and plans the move. Prometheus ERP, built on ERPNext, can be hosted in a US cloud region through our cloud services. For a structured comparison, use how to evaluate ERP options.
Sources and further reading
Product capabilities and guidance change. These are the primary sources this article relies on, checked on the review date above.
- Tax information for businesses, Internal Revenue Service
- Privacy and security guidance for businesses, Federal Trade Commission
- Computer Security Resource Center, National Institute of Standards and Technology (NIST)
- What is ERPNext?, ERPNext documentation (Frappe)
This article is general information, not legal, accounting or security advice for your specific situation. Examples are hypothetical unless stated otherwise.