Moving to Spain. Can I send my negatives in the container?

[Kingwood]

Your question is still relevant for anyone planning a move with delicate items like negatives. Moving to Barcelona must have been quite an adventure!
To address your concerns about humidity during a sea shipment, it's crucial to take precautions. Your current packaging plan with Print File sleeves, Vue-All boxes, and cardboard boxes is a good start. Adding moisture-absorbing packets or desiccants within the cardboard boxes can further help maintain a dry environment for your negatives.
As for me, I'm also preparing for a move, but I'm exploring pricey places in London as a potential destination.

[Jim Andrada]

When we moved back (well, back for me, to for my Japanese wife) to the US from Japan we had all of our household stuff and one of her full size grand pianos in a container. It arrived exactly on schedule and no damage whatsoever. Our doggie came by air. Small problem - our doggie was a full grown Great Dane and had to come on a cargo flight because his custom made aluminum air transport kennel was too large for a passenger aircraft. Just as we were driving up to our Silicon Valley house the pet transport arrived and he was just fine.

[Tim Meisburger]

I shipped all my stuff from Bangkok to the US, then back a year later, then back to the US five years after that. No problem. The only problem I've had with negatives is when I stored them in an attic. Don't do that...

[bomzi]

Well, we moved successfully in January.
I did not pack the negatives in the container but carried them with me on the flight. I had to take them out of their plastic dust free boxes though.
Still, everything arrived safely.

[Jim Andrada]

Glad to hear that everything went smoothly. Moving is always stressful

[Steven Tribe]

If the containers get loose in autumn and winter Storms (Bay of biscay, North sea), no amount of desiccant is going to help!
A view of Jutland’s coast this December.
But usually it is a Secure method (99.995% range!).