FileZilla defaults to allowing up to 10 simultaneous file transfers, but on shared hosting this often causes connection errors, timeouts, and failed uploads. Reducing the number of concurrent connections to 2 or 3 is one of the simplest fixes for FTP reliability issues.
Use 2-3 concurrent connections maximum
Shared hosting servers limit the number of simultaneous FTP sessions per account. Setting FileZilla to 2 or 3 connections prevents timeouts, "421 Too many connections" errors, and temporary IP blocks from the firewall.
01. Why Too Many Connections Cause Problems
Every concurrent transfer in FileZilla opens a separate FTP session to the server. Shared hosting servers typically allow 8 connections per IP address. When FileZilla tries to open more than that, the extra connections are rejected or queued. This leads to timeout errors, "421 Too many connections" messages, and in some cases the server firewall temporarily blocks your IP for making too many rapid connection attempts.
Even if you stay under the server limit, each connection consumes server resources. Two or three connections usually deliver the same real-world speed as ten, because the server's disk and network are the bottleneck rather than the number of parallel streams.
02. Change the Global Setting
This applies to all FTP connections in FileZilla:
- Open FileZilla
- Go to Edit > Settings (on Mac: FileZilla > Preferences)
- Click "Transfers" in the left sidebar
- Set "Maximum simultaneous transfers" to 2
- Click OK
This is the quickest fix and affects all sites you connect to.
03. Change Per-Site Settings
If you connect to multiple servers and want different limits for each, use the Site Manager:
- Open File > Site Manager
- Select your Ultra Web Hosting site (or create one if you have not already)
- Click the "Transfer Settings" tab
- Check "Limit number of simultaneous connections"
- Set the maximum to 2
- Click OK
Per-site settings override the global setting, so you can keep a higher limit for other servers if needed.
04. Recommended Settings for Ultra Web Hosting
For the best experience on our servers, here is what we recommend in FileZilla:
- Maximum simultaneous transfers: 2 (under Edit > Settings > Transfers)
- Connection timeout: 60 seconds (under Edit > Settings > Connection). The default 20 seconds is too short. See fixing FileZilla timeout issues.
- Transfer mode: Passive (under Edit > Settings > FTP). This works best behind routers and firewalls.
- Encryption: Use explicit FTP over TLS for secure transfers
If you are uploading hundreds of small files (like a WordPress installation), a single connection is often faster than multiple connections. The overhead of establishing and managing parallel sessions can actually slow things down when individual files are tiny. For large files (images, backups, databases), 2-3 connections helps.
The same principle applies to all FTP software. In WinSCP, look under Session > Advanced > Connection > Limit connections. In Cyberduck, check Preferences > Transfers > Connections. In SmartFTP, go to Tools > Settings > Transfer > General. We cover more clients in our FTP client guide.
FTP Still Giving You Trouble?
If adjusting connections does not resolve your issue, our support team can check the server side for connection limits or firewall blocks.
Open a Support TicketQuick Recap
- Default 10 connections is too many - Shared servers limit sessions per IP
- Set global limit to 2 - Edit > Settings > Transfers
- Or set per-site - Site Manager > Transfer Settings tab
- Also increase timeout to 60s - Edit > Settings > Connection
- Use passive mode - Works best behind routers and firewalls
Helping users optimize their FTP connections · Last updated March 2026 · Browse all FTP articles
