Cost of a Slow Shop: What Slow Store Revenue Really Costs

Nobody ever walks into their store, looks at the dashboard, and says "the site feels slow today, let me check the books." Slow store revenue is invisible — it never makes it into the spreadsheet. That's exactly why the cost of a slow shop is misjudged by almost every owner I talk to in WooCommerce groups.

The research is published and consistent. Deloitte Digital measured a 2.1–3.1% conversion lift per 100ms for retail sites. Akamai found 7% of conversions lost per 100ms of load time. I use the conservative floor — 0.4% of conversions per 100ms of TTFB above 200ms — because I'd rather my numbers survive an argument in the comments than win one in the clickbait.

The short version: if your shop takes 800ms+ to answer the first request, the cost of a slow shop is roughly 1–3% of revenue, every month, forever. Below are five real store shapes — three in euros, two in dollars — so you can find the one that looks like yours.

How to read the scenarios

The multiplier is simple: conversion loss per 100ms over the 200ms baseline, applied to monthly revenue. A 1.5s TTFB means 1.3 seconds over baseline = 13 buckets of 100ms = 5.2% conversion loss at the conservative floor. These aren't worst cases — they're the floor. The Deloitte numbers suggest 3–5× more.

Scenario 1 — the mid-range €6,000/month shop (800ms TTFB)

A €6,000/month boutique on a typical shared host is handing back €1,728/year before the year even starts. We noticed this exact shape at mitjavilaslowshop.com, a Catalan fashion store we measured with a 4.6s TTFB — in that case the loss is roughly 17% of revenue, or €1,020/month if it books €6,000. The number is not theoretical.

Scenario 2 — the artisan €3,500/month shop (600ms TTFB)

€672/year is not going to break the shop. But note the arithmetic most owners get wrong: the fix costs less than the leak. A managed WooCommerce host fixing the TTFB entirely is typically €10–20/month. That's €120–240/year to reclaim €672. The cost of a slow shop is four times the price of not having one.

Scenario 3 — the late-evening impulse shop, €2,000/month (1.2s TTFB)

Impulse purchases are the most speed-sensitive revenue there is. A 1.2s start means the panel of browsers deciding between your shop and a competitor is making that decision on a slow-loading page. €960/year quietly gone — and this shop would never notice because the sales just don't show up.

Scenario 4 — the $10,000/month US shop (900ms TTFB)

This is the single most common shape on the Revenue Leak Detector: the mid five-figure store on hosting picked because it was cheap, now paying for it in slow store revenue it never sees. $3,360/year is a full marketing campaign, a part-time hire, or the entire profit margin on dozens of orders. And this is the conservative floor — Deloitte's mid-range math puts it closer to $8,000–12,000.

Scenario 5 — the $4,500/month outlet (1.5s TTFB)

At 1.5 seconds we're past Akamai's breakdown threshold for many shoppers. The 5.2% floor is already painful on a thin-margin outlet — but real-world data says the true number is dramatically higher because of abandoned carts that never even start. Every scenario above uses only the conversion-loss multiplier. It does not count the cart abandonments, the bounces, or the Core Web Vitals ranking hit.

The total cost table

What raises the cost of a slow shop even more

Checkout is where it hurts most. WooCommerce's default checkout does full page reloads for address, shipping, then payment. At 800ms TTFB that's ~2.4 seconds of pure server wait before a customer sees the credit-card field. The abandonment happens right there — silently, in the browser, never logged as a problem.

Core Web Vitals make slow shops invisible. Slow stores get fewer organic visitors before any conversion question even starts. That's a second, compounding revenue loss stacked on the first — lost discovery on top of lost conversion.

Promotional days multiply the damage. On a sale day, traffic spikes 3–5×. Slow shared hosting degrades exactly when the store can least afford it. The 5.2% floor in Scenario 5 becomes closer to real-world numbers the moment a marketing email sends a wave of visitors to a shop that can't keep up.

What a fast shop gets instead

The honest cost-of-trust check

Here's the caveat nobody likes hearing: not every slow shop needs a new host. If your TTFB is under 400ms, the host probably isn't your bottleneck — theme and plugin bloat is. Run PageSpeed Insights first, on your product and checkout pages. If TTFB is over 600ms, the host is the problem, and no plugin cleanup is going to fix a server that answers slowly.

I don't sell hosting. I run the test, rank the fixes by ROI, and let the owner decide. The fastest sequential read on this entire page: the cost of a slow shop sits between one and three percent of revenue at the conservative floor — and the fix typically costs less than one month's leak.

Further reading

• WooCommerce Site Speed & Revenue Lost: The Real Numbers — the full math for one $10K store
• How Slow Hosting Costs You Sales — the general TTFB → revenue calculator
• Cloudways vs SiteGround TCO — 3-year cost comparison including revenue impact
• Best WooCommerce Hosting 2026 — the full ranking of 8 hosts by speed and cost
• What Is Price-Lock Hosting? — hosts that don't spike at renewal