Can I use a thumbprint instead of a signature for the Will?
If you (the Testator) are able to hold a pen to sign and has been using signature for recent documents, then it is very much preferable to hand sign all pages.
However should the Testator be unable to (e.g. illiterate or too weak to), then make sure the same thumbprint is to be used throughout.
Even for Lasting Power of Attorney forms in Singapore, thumbprints are allowed as well!
Important Note:
For Wills that appears to have been signed by a blind or illiterate testator, or if there is some doubt about the signing of the Will, the Singapore court may require a supporting affidavit (i.e. affidavit of due execution) to be filed during probate application after the testator's death. The law firm assisting with the documents for probate application can help prepare this affidavit. You can read more about the affidavits requirement in the Family Justice Courts Practice Directions.