What an Ecommerce Web Design Company Is Actually Selling You

Search for an ecommerce web design company and you will find near-identical advice: review the portfolio, check the platform certifications, confirm they offer ongoing support. It is not wrong. It is just aimed at the part of the project that is easiest to look at.

The visual layer is the smallest durable part of an ecommerce build. Underneath it sit four decisions that outlive any redesign — the platform's economics, the compliance surface at checkout, who can actually use the site, and who owns what when the engagement ends. A vendor who is fluent on all four is doing ecommerce development, not decoration. Judge them there.

Platform choice is a pricing decision disguised as a technical one. Both major hosted platforms charge you extra for using a payment processor other than their own, and that surcharge falls as you pay for higher tiers.

On $50,000 of monthly sales, that 2% band is $1,000 a month — far more than the plan itself. BigCommerce also moves you up a tier automatically once trailing-twelve-month sales pass $30,000 on Core or $100,000 on Growth. No design decision offsets this. A vendor who cannot walk you through the arithmetic for your volume is guessing.

Merchants often assume that using a hosted payment provider moves PCI obligations off their plate. That got less true in 2025. PCI DSS requirements 6.4.3 and 11.6.1 — which require that scripts on payment pages be authorised, integrity-checked and monitored for tampering — stopped being best practice and became mandatory, assessable controls after 31 March 2025.

In practice, every third-party tag your agency drops near checkout — analytics, heatmaps, chat widgets, ad pixels — is now in scope. Ask a prospective vendor how they inventory and monitor those scripts. Most agency sales pages have no answer.

The Department of Justice's stated position is that the ADA applies to the goods and services a business offers on the web, and it points to WCAG as the reference standard rather than issuing a detailed regulation.

The exposure is concentrated in retail. UsableNet's annual lawsuit tracking recorded more than 5,000 US digital accessibility lawsuits filed by the end of 2025, with ecommerce accounting for close to 70% of them — and only 36% of the businesses sued reported revenue above $25 million. Being small is not protection. Ask which standard the vendor builds to and how they test it.

This is the question the comparison listicles never raise, and the one most likely to cost you later. Before signing, get clear answers on four things:

• Who holds the platform, domain, and payment gateway accounts — you, or the agency?
• Do you receive the source code and repository access at handover?
• What performance is committed in writing? Google's Core Web Vitals give usable numbers: LCP under 2.5 seconds, INP of 200ms or less, CLS of 0.1 or less, at the 75th percentile of real visits.
• What happens if you leave — is there a documented handover, or a rebuild?

Portfolios are worth reviewing, but review them for the right thing: open the live sites on a phone, run a checkout, and see how they actually perform. That tells you more than a screenshot. Ours are at our portfolio.