If you are married at the time of your death, your spouse will be the beneficiary of the death benefit unless you elect otherwise. If you wish to designate a beneficiary other than, or in addition to, your spouse, your spouse must consent to waive the right to receive the entire death benefit. Your spouse's consent must be in writing and be witnessed by a notary or Plan representative.
You may appoint one or more beneficiaries by completing and submitting a beneficiary designation form online via the Vanguard website. You may change your beneficiary at any time before your death by completing and submitting a new beneficiary designation form online via the Vanguard website. If you have not named a beneficiary or your beneficiary predeceases you, payment will be made to your surviving spouse, if any, and otherwise in equal shares to your children or their then living issue by right of representation. If you have not named a beneficiary or your beneficiary predeceases you, and you have neither a surviving spouse nor children (or their living issue) at the time of your death, payment will be made to your estate.
If you designate your spouse as your beneficiary and later become divorced, that designation will no longer be valid.