Short answer. Yes. Article 813 says that where several dispositions in a holographic will are signed but undated, and the last disposition carries both a signature and a date, that final date validates the earlier ones, whatever time they were actually written. One dated, signed disposition at the end rescues the undated signed entries above it.
What the law says
When a number of dispositions appearing in a holographic will are signed without being dated, and the last disposition has a signature and a date, such date validates the dispositions preceding it, whatever be the time of prior dispositions.
Civil Code, Article 813 — Several Dispositions on One Occasion. Read the full provision →
What Article 813 provides
Article 813 provides that when a number of dispositions appearing in a holographic will are signed without being dated, and the last disposition has a signature and a date, such date validates the dispositions preceding it, whatever be the time of prior dispositions. A holographic will can grow over time, entry by entry, as the testator thinks of things to add. Ordinarily each disposition needs its own date. This article relaxes that for a run of signed-but-undated entries: a single dated, signed disposition at the foot supplies the date the earlier ones lack.
The condition: each entry must still be signed
The relief has a firm limit worth reading closely. The preceding dispositions must be signed — undated, yes, but signed. What the last entry cures is the missing date, not a missing signature. An entry that is neither dated nor signed is not saved by a later dated one; it falls under the stricter rule for additions and does not take effect. So run through your will and check each entry for the testator's signature. Those that have it and only lack a date are the ones Article 813 protects; those missing the signature too are on different ground.
Why the last date can reach backwards
It may seem odd that a date written last can validate entries written earlier, whatever be the time of the prior dispositions. The logic is that the testator, by signing and dating at the end, adopts the whole preceding sequence as of that final date — he affirms, on that day, that all of it is his will. The exact days the earlier lines were written cease to matter, because the operative date is the one he set when he closed the sequence. This is practical: it lets a testator build a holographic will incrementally without a probate court rejecting it for gaps in dating.
What this means for your will
If your last entry is signed and dated and every earlier entry is at least signed, the earlier entries stand. The weak point to look for is any addition jotted without a signature, and any material written below that final dated signature — dispositions after it need their own date and signature to count. Where the sequence is long or the additions significant, the cleaner course is to rewrite the will fresh, fully dated and signed, so nothing turns on this rule at all. But if you cannot, make sure the final disposition is properly signed and dated.