Short answer. At least three. Rule 76, Section 11 requires that, if a holographic will is contested, it will be allowed only if at least three witnesses who know the testator's handwriting explicitly declare that the will and signature are in the testator's handwriting — with expert testimony available if no competent witness can be found.
What the law says
If a holographic will is contested, the same shall be allowed if at least three witnesses who know the handwriting of the testator explicitly declare that the will and the signature are in the handwriting of the testator
Rule 76, Section 11 — Subscribing witnesses produced or accounted for where will contested. Read the full provision →
What the law says
in the absence of any competent witness, and if the court deem it necessary, expert testimony may be resorted to
Rule 76, Section 11 — Subscribing witnesses produced or accounted for where will contested. Read the full provision →
Three witnesses for a contested holographic will
Rule 76, Section 11 provides that if a holographic will is contested, the same shall be allowed if at least three witnesses who know the handwriting of the testator explicitly declare that the will and the signature are in the handwriting of the testator. Each of the three needs to be someone who actually knows the testator's handwriting and is willing to explicitly declare, before the court, that both the body of the will and the signature on it are genuinely the testator's.
Why contested wills need more witnesses than uncontested ones
The same rule elsewhere allows an uncontested will to be probated on the testimony of fewer witnesses, since there is no dispute to resolve. Once a will is contested, the standard rises specifically for holographic wills to three witnesses who know the handwriting, reflecting that a contest puts the authenticity of the handwriting itself in question and calls for more corroboration before the court accepts it as genuine.
When expert testimony can substitute
The rule also addresses what happens if no competent witness who knows the testator's handwriting can be found: in the absence of any competent witness, and if the court deem it necessary, expert testimony may be resorted to. This is a fallback, not an alternative you can choose freely over live witnesses — it applies specifically when competent handwriting witnesses are unavailable and the court itself considers expert testimony necessary.
The witnesses' testimony must survive scrutiny
Section 11 also addresses what happens if the witnesses produced testify against the will's due execution, do not remember attesting to it, or are otherwise of doubtful credibility: the will may still be allowed if the court is satisfied, from the testimony of other witnesses and the evidence as a whole, that it was executed and attested as the law requires. Producing three witnesses is the starting requirement, not an automatic guarantee that the will is allowed.