Choosing a B2B ecommerce platform is a decision most brands make once every five to seven years, and the platform call is one of the highest-stakes decisions a Shopify B2B agency gets briefed on. The cost of getting it wrong is significant. Lost trade revenue, painful migrations, a sales team forced to work around the platform rather than with it. The cost of getting it right compounds: customer accounts that self-serve properly, sales reps closing more deals because the system supports them, and a foundation that scales as the trade business grows.
This article covers the four platforms UK ecommerce brands realistically shortlist in 2026 (Shopify Plus B2B, BigCommerce B2B, Adobe Commerce, and custom builds) and the framework for picking the right one. It's written from the perspective of an agency that builds on these platforms every week, with the biases that come from that experience disclosed up front. Once the platform decision is made, the next question is how to sequence the build itself, which we cover in our 12-month B2B ecommerce strategy framework.
What B2B ecommerce platforms actually need to do
B2B ecommerce is not B2C with a different price tag. The functional requirements look superficially similar (catalogue, cart, checkout) but the operational reality is different. Trade customers need accounts, not anonymous baskets. Pricing is rarely public; it's customer-specific, contract-driven, tier-based. Orders are repeat, scheduled, sometimes triggered by purchase orders. Approval workflows matter. Payment terms (net 30, net 60) sit alongside card and PayPal. Quote-to-order flows usually sit alongside self-serve.
A platform's B2B credentials depend upon how natively it handles those operational realities, not whether it can render a product page. Most platforms can do the surface. Few do the depth without expensive customisation.
The right platform also has to fit the rest of the stack. ERP integration, accounting tools, CRM, inventory: the platform sits in the middle of an operational web, and integration depth often matters more than headline features. The shortlist below scores each on both.
Shopify Plus B2B
Shopify rebuilt its B2B offering from the ground up in 2023 and has shipped meaningful upgrades every quarter since. In 2026, Shopify Plus B2B is a credible enterprise option for most mid-market brands. Customer accounts with company-level structure, multi-buyer logins per company, customer-specific catalogues and pricing, payment terms, draft orders and quote workflows are all native. Checkout is the same battle-tested checkout that handles the largest D2C brands in the world. The differences between standard Shopify B2B and Shopify Plus B2B matter at scale, but for the brands shortlisting Shopify against BigCommerce and Adobe Commerce, Plus is the relevant tier.
The strengths: speed of implementation (typically 12 to 16 weeks for a mid-market B2B build), the app ecosystem, the design and CX flexibility, and the fact that the platform improves continuously without you paying for upgrades. For brands running both D2C and trade, the ability to consolidate onto one platform with two storefronts is meaningfully valuable.
The limits: very complex catalogue logic (deeply nested customer-specific pricing, contractual rebates, complex bundle logic) sometimes pushes against the platform's architecture and requires apps or custom development. The native B2B feature set is good but not infinite. Brands with operational requirements that are unusually complex or industry-specific should validate fit carefully rather than assume the platform handles everything.
BigCommerce B2B Edition
BigCommerce has positioned its B2B Edition more aggressively than Shopify did historically and has the longer track record on B2B as a result. The platform handles the operational basics well: customer groups, price lists, quote management, multi-storefront. API openness is one of its differentiators. For brands that need to integrate deeply with niche ERPs or legacy systems, BigCommerce is often easier to architect around than the alternatives.
The strengths: integration flexibility, B2B-specific features that have been built rather than bolted on, and the kind of granular control that complex trade businesses sometimes need. Pricing tends to come in below Adobe Commerce and similar to Shopify Plus.
The limits: the UK agency ecosystem is smaller, the design and CX flexibility doesn't quite match Shopify, and the rate of platform innovation has been slower. Brands choosing BigCommerce should verify the agency partner has real BigCommerce B2B experience. The talent pool is shallower than the Shopify equivalent.
Adobe Commerce (formerly Magento)
Adobe Commerce remains the platform of choice for the most operationally complex B2B businesses. Multi-brand groups, distributors with thousands of customer-specific catalogues, manufacturers with complex configure-to-order flows. Its B2B module is deep, with native support for the kind of edge cases the SaaS platforms struggle with.
The strengths: feature depth, customisation flexibility, and the ability to handle operational complexity that would break a SaaS platform. For very large or very complex businesses where platform fit is non-negotiable, Adobe Commerce remains the right answer.
The limits: total cost of ownership is significantly higher than the SaaS alternatives. Licences, hosting, ongoing maintenance and the developer day rates required to maintain a Commerce build add up fast. Implementation timelines are typically 6 to 12 months. A lot of brands historically choosing Magento have re-evaluated in the last two years and many have migrated to Shopify Plus B2B as the feature gap has narrowed. Adobe Commerce is the right answer for genuinely complex operations. Not the default answer for everyone else.
Custom builds and headless
A small minority of B2B businesses still build entirely custom platforms or run headless architectures with a commerce engine (Shopify Plus, commercetools, BigCommerce) and a separately built front-end. The case for going custom is narrower than it used to be. The SaaS platforms have closed the feature gap. But it remains the right answer in specific scenarios.
When custom or headless makes sense: when the storefront experience needs to be properly differentiated and the SaaS templates can't deliver it; when the brand has very complex multi-brand or multi-region requirements that demand highly bespoke front-ends; when a CMS-driven content experience is the centre of the value proposition and the commerce layer is supporting cast. For mainstream B2B operations, custom is rarely the optimal answer in 2026.
The decision framework
The shortlist narrows quickly when scored against three criteria: operational complexity, total cost of ownership including agency support over five years, and the strategic value of speed to market.
For most mid-market UK B2B ecommerce brands launching or replatforming in 2026, Shopify Plus B2B is the right starting point. It handles the operational depth the business actually needs, ships fast, costs less to run than the alternatives over a five-year horizon, and benefits from continuous platform improvements paid for by Shopify rather than the customer. The UK brands doing B2B ecommerce well almost all sit on Plus today. BigCommerce is the right second choice when integration flexibility or specific B2B feature gaps push against Shopify's architecture. Adobe Commerce is the right answer for operationally complex multi-brand or multi-region operations where the SaaS platforms can't deliver the required depth. Custom is rarely the right default.
The selection process matters as much as the shortlist. Map every operational requirement against the platform's native capabilities rather than against the demo. Validate complex scenarios with the agency before signing. Talk to brands using the platform in production and ask about the limits, not the highlights. The platforms all demo well. The operational reality six months in is what determines whether the choice was right.
How Imaginaire approaches B2B platform selection
At Imaginaire, we build primarily on Shopify Plus, and we're upfront about that bias. We've watched the platform mature into a credible enterprise B2B option, and for the brands we work with it's almost always the right answer. But not always. We've talked clients out of Shopify Plus and onto Adobe Commerce or BigCommerce when the operational realities demanded it.
Our B2B ecommerce builds start with platform validation, not platform assumption. We map every operational requirement against the platform's native capabilities, surface the gaps that would require apps or custom development, and quantify the implications before committing. The build itself usually takes 12 to 16 weeks on Shopify Plus B2B for a mid-market brand.
If you're early in the platform decision and want a second opinion grounded in real build experience rather than vendor-biased product pages, we'd be happy to put together a free platform audit covering your operational requirements, the gap analysis, and a recommendation.
