An A-B trust, also called a bypass trust, is a two-trust structure commonly created by a married couple to manage wealth transfer at death. This legal tool can help to minimize the impact of estate taxes, support control over asset distribution, protect assets from creditors and better ensure provisions for a spouse and children from a previous marriage.
How an A-B trust works in an estate plan
At the death of a spouse, the estate divides into two shares. The “A” trust is typically the survivor’s trust. The “B” trust is the bypass, credit shelter, or family trust. Assets allocated to the B trust are generally excluded from the surviving spouse’s taxable estate, subject to applicable law. The surviving spouse may receive income and limited principal from the B trust based on the language used to create the trust. The remainder passes to named beneficiaries at the survivor’s death, often children or descendants of the first spouse to die.
Control over asset distribution
A bypass trust essentially locks in the first spouse’s plan for distribution of their portion of the estate. That legal effect matters when later life events introduce pressure, new relationships, incapacity, or uneven family dynamics. Typical control mechanisms include:
- Distributions based on certain milestones such as reaching a specific age, going to college, or buying a home.
- Trustee discretion as guided by the language of the trust often for health, education, maintenance and support of the beneficiaries.
- Protections to retain assets for children as named in the trust.
These terms are intended to reduce the risk of unintended disinheritance while preserving access for the surviving spouse through defined rights.
Asset protection and creditor exposure
A bypass trust may limit exposure to claims against the surviving spouse, depending on state law, trust terms, and the nature of the claim. Common creditor risks that may apply in these situations can include those arising from medical costs or business liabilities.
This is not absolute immunity. Fraudulent transfer rules, support obligations and trustee misconduct can defeat protection.
Managing blended families
Blended families often involve competing obligations to a surviving spouse and to children from a prior relationship. A bypass trust helps to support a balanced legal arrangement. The surviving spouse can have lifetime benefit, often income and limited principal while the children can receive a protected remainder. The trustee’s fiduciary duty adds oversight that a simple outright transfer lacks.
A-B trusts remain a valuable planning tool when estate tax exposure, creditor concerns, or blended family structure call for an additional level of control. The strategy requires careful coordination with beneficiary designations, titling, state tax law and funding steps. Periodic review is essential as exemption amounts, family circumstances and when the laws that guide estate tax exemption change.