Unfunded commitment
Also called uncalled capital, undrawn commitment, uncalled commitment, dry powder.
Unfunded commitment is the portion of a limited partner's capital commitment that the fund has not yet called, calculated as total commitment less contributions to date plus any distributions the LPA makes recallable, and represents the LP's remaining obligation to fund capital calls.
Example
An LP commits $8M to a fund. Over three years the fund calls $5.2M. It then distributes $300,000 to the LP flagged as recallable. Unfunded commitment is $8M less $5.2M plus $300,000, or $3.1M. That is the most the fund can still ask the LP for. The LP's total exposure to the fund for planning purposes is their capital account, say $5.9M after gains, plus the $3.1M unfunded, or $9M.
Confused with
Capital account. The capital account is what has happened: money in, gains and losses allocated, money out. Unfunded commitment is what has not happened yet.
Follow-on reserve. A reserve is the GP's plan for how it intends to use the fund's unfunded commitments. Unfunded commitment is the LP's legal obligation whether or not there is a plan for it.
In practice
Unfunded commitment is the number a subscription line lender advances against, the number an LP uses to manage its own liquidity, and the number a default is measured against. It should agree between the fund's records, the capital account statement and the LP's own books every quarter. The usual causes of a mismatch are recallable distributions, equalisation at a later closing and fees called outside the commitment.