Short answer. Each of you answers for the whole of it. Where two or more people borrow one thing under the same contract, the Civil Code makes them solidarily liable, so the lender may recover everything from any one of them. Whoever pays can then pursue the others for their shares.
What the law says
When there are two or more bailees to whom a thing is loaned in the same contract, they are liable solidarily.
Civil Code, Article 1945 — Solidary Liability of Bailees. Read the full provision →
One line, with a long reach
Article 1945 says simply: When there are two or more bailees to whom a thing is loaned in the same contract, they are liable solidarily. A bailee here is a borrower in a free loan of a thing — what the Code calls commodatum. Solidary liability means each borrower answers for the whole obligation, not for a share of it. If three friends borrow one vehicle under one agreement and it is wrecked, the lender may demand the entire amount from any one of them, and that one cannot insist the lender collect a third from each instead.
It allocates a loss, not blame
This catches people by surprise, so it is worth saying plainly. The rule does not declare that whoever was holding the thing at the time is the guilty one, and it does not excuse a borrower who never so much as touched it. Everyone who came in on the same loan carries the whole risk. The reasoning is that the lender parted with his property once, to a group, usually for nothing in return, and should not have to reconstruct which of them dropped it before he can be made whole. Sorting that out is put on the borrowers, who were actually there.
The one who pays is not left carrying it
Paying in full is not the end of the story. Solidary liability governs the relationship with the lender; among the borrowers themselves, the one who paid may seek contribution from the others for their respective shares. That is his own separate claim and it lives or dies on evidence — who borrowed, on what terms, and who caused the loss. It is a good reason to keep the messages that arranged the loan. It is also a reason to think before signing on behalf of a group: you may fund the entire loss first and argue about it afterwards.
The limits of the rule
Two conditions matter. The article applies where the thing was loaned in the same contract, so separate loans to separate people — even of the same item at different times — are a different situation. And it governs how the liability is shared, not whether there is liability at all; whether anyone must pay for the loss depends on the rules on a borrower's duty of care. If you are being asked to pay for the whole of a shared borrowing, keep the agreement, identify the others, and take advice promptly, as claims of this kind are subject to time limits.