How is the 6 foot sink measurement taken?

NEC 210.8(A)(7) measures 1.8 m (6 ft) from the top inside edge of the bowl of the sink, not from the faucet or the edge of the countertop.

Does a garbage disposal receptacle need GFCI protection?

In a dwelling unit, yes, because the receptacle sits within 6 feet of the sink bowl and is covered by NEC 210.8(A)(7).

Can the GFCI device be inside the sink cabinet?

The 2023 NEC requires GFCI devices to be readily accessible. A device crammed behind a disposal is not, so protecting the circuit at the panel or at an accessible upstream receptacle is the safer choice.

Does a receptacle under a sink need GFCI protection?

In a dwelling unit, almost always yes. The measurement rule in Section 210.8(A)(7) of the 2023 NEC catches virtually every receptacle inside a sink base cabinet, and the appliance rules in 210.8(D) catch the disposal and the dishwasher on top of that.

The 6 foot rule

Section 210.8(A)(7) requires GFCI protection for 125 volt through 250 volt receptacles installed in dwelling units where they are located within 1.8 m (6 ft) of the top inside edge of the bowl of a sink. The measurement is taken from the top inside edge of the bowl, not from the faucet and not from the edge of the counter. A receptacle mounted on the cabinet wall directly below the bowl is maybe 18 inches away, so it lands inside the 6 foot radius without any argument.

People sometimes assume the rule only applies to receptacles above the counter. It does not. Section 210.8(A) applies to receptacles in the listed locations regardless of height, and 210.8(A)(7) is written around proximity to the sink bowl, not around countertop surfaces. The kitchen countertop rule is separate and lives in 210.8(A)(6).

The appliance rule stacks on top

Section 210.8(D) of the 2023 NEC requires GFCI protection for the outlets supplying specific appliances rated 150 volts or less to ground and 60 amperes or less, single or three phase, in dwelling units. Dishwashers are on that list. So even if you somehow got a dishwasher receptacle more than 6 feet from the sink bowl, 210.8(D) still requires the protection. A garbage disposal fed by a receptacle under the sink is caught by 210.8(A)(7) because of its location.

Where to put the GFCI device

Section 210.8 requires the protection, not a particular device location. Common approaches are a GFCI breaker at the panel, a GFCI receptacle in the cabinet, or a GFCI receptacle upstream on the same circuit feeding the under sink receptacle through its load terminals. Note that Section 210.8 in the 2023 edition also requires GFCI devices to be in a readily accessible location. A GFCI receptacle buried behind a garbage disposal in the back of a cabinet is a reset button nobody can reach, and inspectors do call that out. Protect the run from a breaker or from an accessible upstream device instead.

Commercial and other than dwelling

For other than dwelling units, Section 210.8(B)(5) covers sinks, requiring GFCI protection for receptacles installed within 1.8 m (6 ft) of the top inside edge of the bowl of a sink. Same distance, different subsection, so a break room sink base cabinet in an office follows the same logic.

Field takeaway

Measure 6 feet from the top inside edge of the bowl. If the receptacle falls inside that, it needs GFCI protection under 210.8(A)(7). Put the device somewhere a homeowner can actually reach it, which usually means a GFCI breaker for the disposal and dishwasher circuits.