Replatforming sounds straightforward at first. You move your data, recreate your storefront, connect a few systems, and launch on a new foundation. In reality, the timeline depends on how your business operates, how clean your data is, and how much of your current setup needs to be rebuilt in Magento Open Source.
There is no universal number that applies to every store. The duration is shaped by complexity, not a template. A migration done properly protects your data, avoids downtime, and ensures the new site functions as expected on day one. Rushing the process creates problems that are far more expensive to fix later.
This post outlines the key factors that influence timing so you can plan the transition with clarity instead of guesswork.
The Five Factors That Determine the Timeline
The length of a Magento migration depends on what your current store looks like and how much of it needs to be rebuilt or improved. Here are the factors that carry the most weight.
- Data complexity
Your product catalog, variants, customer records, order history, and custom attributes all influence the timeline. Clean and well-structured data moves quickly. Inconsistent or incomplete data slows everything down.
- Design and user experience
Some teams want a simple theme that mirrors their current store. Others use the migration as an opportunity for a refreshed design. A full redesign adds more time than a theme-based approach.
- Custom functionality
Many platforms rely on built-in apps or plugins to create custom workflows. These functions need to be recreated or replaced in Magento. The more specialized your logic is, the longer the build takes.
- Integrations with other systems
ERPs, CRMs, 3PLs, marketing platforms, and fulfillment systems each require planning and testing. Complex integrations often extend the migration window.
- Replacing existing apps
SaaS platforms depend heavily on app ecosystems. Each app represents a feature that needs to be mapped, rebuilt, or replaced in Magento. The more apps you depend on, the longer the transition.
Typical Timeline Ranges Based on Store Complexity
Every migration sits somewhere on a spectrum. The timeline depends on how much work is required to recreate your current experience in Magento and how many systems sit around it. These ranges are safe, realistic, and consistent with what most agencies deliver.
- Simple Stores. A smaller catalog, limited custom functionality, and only one or two basic integrations fall into this category. These projects usually take eight to twelve weeks when the data is clean and the design requirements are light.
- Mid-Complexity Stores. Larger catalogs, more advanced workflows, multiple integrations, and a higher level of customization require more time. These projects usually take twelve to twenty weeks, depending on how much needs to be rebuilt.
- High-Complexity or B2B-Driven Stores. Custom quoting, account structures, advanced pricing, multi-store setups, ERP dependencies, or heavy operational workflows add significant scope. These projects often extend beyond twenty weeks because every part of the system needs careful planning, mapping, and testing.
These ranges help set expectations, but the real timeline comes from the specifics of your platform, your data, and your internal processes.
What Happens During a Magento Migration
A proper migration follows a structured sequence. Each phase builds on the one before it, which keeps the project predictable and prevents issues at launch.
- Discovery and Planning. This is where requirements are documented, your current platform is reviewed, data is analyzed, and the scope becomes clear. A strong discovery phase reduces surprises later.
- Design or Theme Development. Some merchants choose a theme for speed and simplicity. Others want a custom design. This decision affects the timeline, but the process is always focused on creating a storefront that supports your business needs.
- Build and Configuration. The core Magento setup happens here. Catalog structure, store settings, checkout rules, tax and shipping configuration, and any required custom functionality are implemented in this phase.
- Integrations. External systems such as ERPs, CRMs, 3PLs, and marketing platforms are connected and tested. The amount of integration work is one of the biggest factors influencing the overall timeline.
- Data Migration. Your products, categories, customers, orders, and URLs are mapped and imported. Clean data moves quickly. Inconsistent or incomplete data requires more preparation.
- Quality Assurance and Testing. Every feature, workflow, and integration is tested to ensure a smooth launch. This includes performance checks, checkout testing, and user acceptance testing.
- Launch and Stabilization. Once testing is complete, the site is deployed and monitored closely. Teams address any minor issues that arise and ensure operations are stable.
A well-planned migration makes launch day predictable instead of stressful.
What Speeds Up or Slows Down the Timeline
The timeline for a Magento migration is shaped by how prepared the business is and how complex the current setup has become. Some factors move the project faster, while others add unavoidable time.
Teams move quickly when their data is clean, their requirements are clear, and they are open to using a theme instead of building a fully custom design. Limited integrations also shorten the timeline because there are fewer systems to coordinate and test.
And on the flip side, larger catalogs with inconsistent data create delays because they require cleanup before migration. Stores that rely heavily on SaaS apps need time to rebuild those functions in Magento. Integrations with ERPs or fulfillment systems also add complexity, as do multi-store environments or specialized workflows.
Understanding these variables early helps set a realistic plan and prevents surprises once the migration is underway.
The Risk of Rushing a Migration
Fast timelines sound attractive, but shortcuts often create problems that surface long after launch. A rushed migration can miss important data, break existing workflows, or introduce performance issues that take more time and money to fix later.
Skipping proper data mapping is one of the most common mistakes. When data is moved without a full review, customer accounts, order history, or product information can come across incomplete or incorrect. Checkout flows and integrations can also break if they are not tested thoroughly.
Performance and security work are other areas that suffer when teams move too fast. Magento needs proper configuration to run smoothly, and cutting corners here leads to slow load times or stability issues once traffic increases.
A migration should move efficiently, but not at the cost of quality. A careful approach avoids the setbacks that come from trying to launch ahead of schedule.
What a Proper Migration Delivers and Where to Go From Here
A well-executed migration gives your business more than a functioning Magento store. It creates a stable foundation built around clean data, reliable workflows, and integrations that support your daily operations. The checkout runs smoothly, performance is consistent, and the system is set up in a way that makes future improvements easier instead of harder.
When the process is planned correctly, you launch with confidence. Nothing feels rushed or unpredictable. You know how the store works, how the data flows, and what the platform can support as you grow.
If you want clarity on what a migration would look like for your business or need a realistic timeline for your specific platform, the team at Bighorn can walk you through it.
We help merchants transition into Magento Open Source with a plan that protects their data, reduces risk, and sets them up for long-term stability. Schedule a free discovery call.