MikroTik load balancing methods: PCC, ECMP, Nth and bonding compared
Last updated: 11 October 2026
MikroTik offers several ways to use two or more internet lines. They differ in how much control you get and in what breaks. For most small ISPs and offices the answer is PCC, but it helps to know why.
At a glance
| Method | How it splits | Good at | Watch out for |
|---|---|---|---|
| PCC | Each connection, by a hash of addresses (and ports if you choose) | Control, weighting, works on v6 and v7, keeps a user on one line per site | More rules; FastTrack must be off |
| ECMP | Several equal routes; the router spreads connections itself | Very little configuration | Little control over who uses which line; check behaviour on your version before relying on it with NAT |
| Nth | Every Nth new connection to the next line | Even counts | The same user's connections to one site can use different lines, which breaks some logins |
| Bonding | Joins links into one | One connection can be faster than one link | Needs the other end to bond too: two links between your own routers, not two providers |
| Failover only | All traffic on line 1, line 2 waits | Simplest, nothing to break | The second line is paid for and idle |
PCC
Per connection classifier puts each new connection in a class, and you decide which line each class uses. With both-addresses the class comes from the user's address and the destination address, so the same user stays on the same line for the same site. That is what banks and online games expect. Weighting is easy (more classes for a faster line), and the same rules work on PPPoE lines and with three or four lines.
ECMP
Equal-cost multi-path: two default routes with the same distance, and the router itself spreads traffic between them. It is a couple of lines of configuration, but you cannot say which user goes where, and the details differ between RouterOS versions. Use it where both paths lead to the same network (two links between your own sites) rather than to two providers with NAT.
Nth
The nth matcher counts new connections and sends every second (or third) one to the next line. Counts are perfectly even, but a website that opens several connections sees them come from two addresses, and some sites log the user out. PCC solves the same problem without that side effect.
Bonding
Bonding joins several links into one interface, for example two radio links between your tower and your office. It only works if both ends take part, so it does not join two internet providers.
Which one?
- Two or more providers, users behind NAT: PCC, plus a spare route per table for failover. The free script generator writes it for two lines.
- One good line and a backup: failover.
- Two links between your own routers: bonding or ECMP with routing.
- Only some users or devices on the second line: policy-based routing.
Questions and answers
Which is better, PCC or ECMP on MikroTik?
For two internet providers with NAT, PCC: it gives control over who uses which line and keeps each user on one line per site. ECMP suits equal paths between your own networks.
Does load balancing double the speed of one download?
No. Every method except bonding sends each connection over one line. The total capacity for many users goes up.
Why do some websites log me out with load balancing?
Their connections are reaching the site from two different addresses. Use PCC with both-addresses so a user stays on one line per site.