Bandwidth Limit Exceeded
Production Risk
High — the entire website is inaccessible until bandwidth is reset or upgraded.
509 Bandwidth Limit Exceeded is an unofficial code used by Apache web servers (often on shared hosting via cPanel) to indicate that the website has exceeded its allocated monthly bandwidth quota. The hosting provider blocks further traffic until the quota resets or is increased.
- 1The website has consumed all of its monthly bandwidth allowance on a shared hosting plan.
- 2A viral piece of content caused a sudden spike in traffic.
- 3Large file downloads (videos, installers) consumed the bandwidth quota quickly.
- 4A DDoS attack consumed the site's bandwidth budget.
A shared hosting website goes viral and exhausts its monthly 10GB bandwidth limit within days.
GET /large-video.mp4 HTTP/1.1 Host: mysite.cpanel-host.com # Monthly bandwidth quota exhausted
expected output
HTTP/1.1 509 Bandwidth Limit Exceeded
Fix 1
Upgrade the hosting plan to increase bandwidth quota
WHEN Legitimate traffic is the cause.
# Contact hosting provider or upgrade via cPanel account settings
Why this works
Increases the monthly bandwidth allowance, allowing traffic to resume.
Fix 2
Move large assets to a CDN
WHEN Large file downloads are consuming bandwidth.
# Move static assets to S3 + CloudFront or similar CDN # CDN bandwidth is typically much cheaper than shared hosting
Why this works
Offloads bandwidth-heavy content to a CDN, preserving the hosting quota for HTML/API requests.
✕ Do not serve large media files directly from shared hosting
A single popular video can exhaust a month's bandwidth quota in hours.
Specific to shared hosting providers using cPanel. Not a standard IETF code.
Apache/cPanel hosting documentation
https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#509 ↗Content generated with AI assistance and reviewed for accuracy. Found an error? hello@errcodes.dev