I intend to marry under the separate property regime (séparation de biens). If I personally finance renovation works in our main residence, which is solely owned by my spouse, will I be able to recover my funds in the event of a divorce?

Yes. In the context of a divorce, financial adjustments may be made between spouses. If you have used personal funds to improve a property that belongs exclusively to your spouse, you may assert a claim (créance) against them. This is governed by Articles 1478 and 1479 of the French Civil Code, which allow for the recognition of such claims between spouses under the separate property regime. However, you will need to provide evidence of both the works carried out and the source of your financing.