The honest TL;DR

Pick custom code when you want fast load times, strong SEO, and minimal monthly fees, and your content changes infrequently. Pick WordPress when non-technical editors need to update content weekly, you have a content team that already knows it, or you specifically need a WordPress plugin like WooCommerce. Both can ship great work — the wrong tool for your context will hurt you whichever you pick.

Disclosure: WebSilm builds with both. About a fifth of our work is WordPress (usually on inherited sites or where a client genuinely needs WooCommerce); the rest is custom code on static-first stacks. We don't have a horse in this race. What follows is the framework we actually use when a small business asks us which way to go.

When WordPress wins

WordPress is the right pick when one or more of these is true:

When custom code wins

Custom code is the right pick when:

5-year total cost: the table everyone wants but few publish honestly

Numbers below are typical ranges from real WebSilm projects, plus public WordPress hosting / plugin pricing. Your numbers will vary.

Cost item Custom code (WebSilm) WordPress (typical agency)
Year-1 build €500 – €2,500 €1,500 – €4,000
Hosting (year 1) €0 – €60 (Cloudflare Pages free tier) €80 – €240 (Kinsta, WP Engine, SiteGround)
Premium plugins (year 1) €0 (none needed) €100 – €400 (Yoast Premium, WP Rocket, security, backup)
Maintenance (years 2–5) €0 – €240 total (occasional fixes) €400 – €1,600 total (€100–400/yr update + security)
Hosting + plugins (years 2–5) €0 – €240 total €720 – €2,560 total
5-year total €500 – €3,040 €2,800 – €8,800

The gap closes for very content-heavy sites where custom builds need a small CMS layer (Sanity Studio, Notion API, or Decap CMS). It widens for marketing sites that change once or twice a year.

Performance: what real measurements show

HTTP Archive's annual Web Almanac tracks Core Web Vitals across millions of sites. The 2025 report (most recent at writing) shows:

Metric Custom static (avg) WordPress (avg)
Largest Contentful Paint (LCP) 0.8 – 1.4s 2.4 – 3.8s
Cumulative Layout Shift (CLS) 0.02 – 0.06 0.08 – 0.18
Interaction to Next Paint (INP) 80 – 150ms 180 – 380ms
% of mobile sites passing all 3 thresholds 78 – 84% 22 – 30%

The performance gap isn't WordPress's fault per se. It's the cumulative weight of the average WordPress install: 2–3 themes installed (with one active), 15–25 plugins each loading their own CSS / JS, an admin bar, render-blocking jQuery, and image-heavy hero sliders. A carefully tuned WordPress site on a fast host can hit Core Web Vitals — but it takes work the typical small-business owner can't audit.

Three real scenarios

Scenario 1: SaaS marketing site, 8 pages, content updates twice a year

Custom code wins. The site exists to convert visitors. Speed and SEO are the actual product. Content changes are infrequent enough that a developer retainer is cheaper than CMS overhead. WordPress here would mean fighting the platform to hit the load times the conversion rate needs.

Scenario 2: Restaurant with weekly menu and event updates

WordPress wins (or a CMS-backed custom build). The owner publishes weekly. Asking a developer to deploy each menu change costs more in friction than the CMS overhead saves. WordPress + a clean theme + a couple of carefully chosen plugins is genuinely the right tool here. Or — a custom static site backed by a tiny CMS like Sanity or Decap, which gives you both: editor experience + speed.

Scenario 3: Local plumber / electrician / tradesperson

Custom code wins. A 3-to-5 page site with services, area-served, contact form, and reviews. Updates rarely. The customer journey ends in a phone call or contact form, not a content browse. Pay €600 once, host for free, never think about it again. WordPress here is over-engineering for the use case.

The decision framework

Three honest questions to ask yourself
  1. Will a non-developer publish content more than twice a month? If yes, lean WordPress (or a CMS-backed custom build). If no, lean custom code.
  2. Is page speed measurable in your conversion rate? If yes (B2B SaaS, e-commerce, high-intent landing pages), custom code is usually worth it. If no (informational, local services), either works.
  3. Do you specifically need WooCommerce, LearnDash, or another flagship plugin? If yes, WordPress. The plugin ecosystem is real value.

What to ask any agency before they sell you either

Bottom line

For most small businesses we work with at WebSilm — service businesses, SaaS marketing sites, agency portfolios — custom code wins on a 5-year horizon, mostly because we keep ongoing costs near zero through static hosting on Cloudflare Pages. WordPress remains the right choice for content-heavy sites with non-technical editors who publish weekly. Both platforms can ship great work; the wrong tool for your context will hurt you whichever you pick. The framework above will get you 80% of the way to the right answer for your situation.

If you're stuck on the decision and want a sanity check, we offer a free 30-minute scoping call where we'll honestly tell you which way to lean — sometimes that means recommending you don't hire us at all. No sales pitch, no follow-up emails.