What is a WIBON clause, and why it matters at a congested anchorage
A WIBON clause, short for "Whether In Berth Or Not," lets the master tender Notice of Readiness from the anchorage instead of waiting for the vessel to reach berth. It's one line in the charterparty, but at a congested port it decides who eats the queue: the owner or the charterer.
Without WIBON, laytime typically can't start until the vessel is all fast at berth, or at least within the fiscal/customs limits the charterparty defines as "arrival." If the terminal is backed up and the ship sits at anchor for twelve days waiting for a slot, that wait falls on the owner's side of the ledger. Nobody's counting laytime yet. With WIBON in the fixture, NOR tendered at the anchorage is valid NOR, and laytime (or time counting toward demurrage, depending on how the clause interacts with the rest of the laytime provisions) starts running whether or not a berth is actually open. The congestion risk flips to the charterer.
Why this clause gets fought over at the fixing stage
Owners push for WIBON on any voyage touching a port with a known congestion problem, because they've been burned before by vessels idling for a week-plus at anchor with the clock not running. Charterers resist it for the same reason in reverse: they don't want to pay demurrage for berth delay that has nothing to do with their cargo readiness or their receivers' performance. The compromise language you'll see in practice includes things like "WIBON, WIPON, WIFPON, WICCON" stacked together (berth, port, free pratique, customs clearance, all "or not"), each one closing off another reason NOR might otherwise be rejected as premature.
The clause interacts with whatever NOR-tendering provision sits elsewhere in the charterparty too. A vessel can be WIBON and still have its NOR rejected if it hasn't arrived within the geographic or legal limits the fixture defines as the port, or if it hasn't got free pratique where that's a condition precedent. So WIBON on its own doesn't guarantee laytime starts the moment the anchor goes down. It just removes "the berth wasn't free" as the agent's objection.
Where this bites: the anchorage, not the fixture note
The clause reads fine on paper. The exposure shows up three weeks later, when the agent's telex finally reports a queue of thirty vessels and a laycan that's slipped past the point of no return. By the time that update lands, the charterer has already accrued ten or twelve days of demurrage they didn't see coming, because the only visibility into anchorage conditions was the agent's word, updated whenever the agent got around to it.
That gap between what's happening at the anchorage and when the desk hears about it is the real commercial problem. The charterparty already settled whether WIBON applies; what's missing is a clean read on how many ships are queued, and whether that queue is growing or clearing, before the agent's update shows up.
Reading the queue before the agent does
A charterer running several WIBON fixtures into the same congested range benefits from watching the anchorage directly rather than waiting on port reports. A rising vessel count at anchor outside a port is the leading indicator for exactly the kind of berth delay that WIBON shifts onto the charterer's book. Catching that build-up early, days before the agent's telex confirms it, is what lets a desk push back on a laycan, re-nominate, or just size the demurrage provision correctly before it's a surprise on the final statement.
That's the gap Port Congestion Watch is built for: a daily anchorage count, tracked over time into a congestion series, so a charterer can see the queue building at a specific port before the paperwork catches up.
If a WIBON clause is already sitting in your fixtures on a congested range, start tracking that anchorage before the next telex update does it for you.