Check baggage the night before in Lisbon?

Calling them or checking their website would give you the best, reliable answer.

Calling gets me on h
old for a long time and I have certainly already tried the website. It only mentions Heathrow, as far as I can tell. I was simply hoping someone already knew the answer.

To store your baggage

Left Luggage

If you have some time to visit Lisbon but are travelling with a lot of baggage or with bulky items, such as a bicycles, surfboards, or several bags per passenger, no worries. With us, your baggage will be safe for as long as you need.

Left Luggage Service is temporarily closed.

(https://www.aeroportolisboa.pt/en/lis/services-shopping/essential-services/baggage-services)

I suspect if the baggage hold service is closed the prospect of night before bag drop off with BA is not promising

If the BA website does not have the answer, and waiting on the phone is not practical, try an email (https://www.britishairways.com/travel/askbainter/public/en_us )

They also do twitter ( You can also get in touch with us on Twitter @British_Airways. )

At the very least at Munich, checking in the night before is not available for US-bound flights, for security reasons. Since we can't lock our bags, airport staff doesn't want to be liable for lost items.

However, I agree that your best bet is to call the airline. Call a few times and talk to a few agents to reconfirm. Many a time, only the local airport staff can give an absolutely correct answer. I had this experience in Zurich. I carried my large suitcase to the airport the night before but was turned down by Delta ground staff, despite being told by phone agents in the US that it was ok to check-in early.

For security reasons, most (all?) airlines will not accept luggage the day before, most even limit it to four hours early.

I assume the reason you want to check the night before is to save some time in the morning, if so, the "left luggage" option mentioned would not work. it would take more time to retrieve your luggage, then check it in, as opposed to just showing up and checking it. The left luggage office will not check your bags into your flight, it only holds the bags someplace secure until you pick them up. If it is just a matter of not wanting to lug them around...then it might work, just more time consuming.