...Once funds are appropriated, Congress expects that these funds will be used during the fiscal year for which they are appropriated. Congress must enact annual appropriations bills prior to the beginning of the each fiscal year (October 1) or provide interim funding for the affected programs through a "continuing resolution." Sometimes, the Congress will combine several appropriations bills at the end of the year and pass them all together as an "omnibus."
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How does the appropriations process work?
An appropriations bill is considered in much the same way as other bills that pass through Congress. It is introduced by Members of the House and Senate, subcommittee hearings are held, subcommittees and committees amend the bills and vote on them, they are considered by the full House and Senate and votes are taken, a conference committee is appointed to reconcile differences between the two chambers' versions, and the conference report (i.e. the final bill) is then voted on by the House and Senate and sent to the President for signature or veto.
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The House starts voting on appropriations bills in May and seeks to complete this by the August district work period. In recent years, however, many of these votes have not occurred until the fall. The Senate may begin committee work on its 11 spending bills and may even vote on the bills before the House completes its work.
After the House and the Senate have each voted on its versions of an appropriations bill, a conference committee meets. That committee consists of equal number of House and Senate members who reconcile any differences between the spending bills.
The conference committees make the final decisions on bills and reconcile the differences. The conference report is then sent to both the House and Senate for approval. If approved, it is then sent to President. After the President signs a bill, each impacted department or agency reviews the bill, makes the regulatory changes mandated by Congress and begins allocating the funding to appropriate departments and projects referenced in the bill. When there is a direct appropriation to an outside entity, the agency will usually allocate funding to the organization or community in the spring (mid-March through May).