I'm currently trying to understand H.R.3684 - Infrastructure Investment and Jobs Act (IIJA) but there are a few things don't understand.

Authorization vs. Appropriation

As far as I understand, authorization is some sort of legal foundation. If spending is discretionary (?) every year in budget negotiations, congress debates how much money they should appropriate to each program out of the amount authorized. However, in the current bill there are a Lot of additional appropriations in the last segment (Division J). So some programs, for example Northeast-Corridor Amtrak funding, gets appropriations for the full timespan (22-26) that are higher than the authorized spending in the specific segment of the bill.

How can I interpret those numbers?

Is it that those amounts appropriated in the appropriations segments are guaranteed spending and those numbers in the authorization segments are additional possible spending in each year, or is it something else?

  • 2
    In the future, when a question of yours gets closed, it is better to edit the closed question to address the reasons it was closed, and allow the community to reopen it.
    – Joe C
    Oct 26, 2021 at 7:32

2 Answers 2


The Congressional Research Service published a document back in 2012 that explains the difference. They describe authorization as:

An authorizing measure can establish, continue, or modify an agency, program, or activity for a fixed or indefinite period of time. It also may set forth the duties and functions of an agency or program, its organizational structure, and the responsibilities of agency or program officials.

They describe appropriation as:

An appropriations measure provides budget authority to an agency for specified purposes. Budget authority allows federal agencies to incur obligations and authorizes payments to be made out of the Treasury

So, basically, an authorization gives an agency the legal authority to perform a type of activity; however, it does not provide any money to spend on the activity. The US Constitution states that in order for the government to spend money on anything, Congress must first provide funds through appropriations legislation.

If you read a bit further in the report, in practice the waters get a little bit muddied. Authorization legislation will sometimes provide guidance on the amount of money to spend on an activity, but that does not obviate the need for an appropriation to actually fund it. Moreover, such guidance is not legally binding (i.e., it can be overridden by an appropriations bill), but it does appear to be enforced in the House and Senate rules of procedure:

First, the House and Senate place restrictions on appropriations for agencies and activities not authorized by law. The House (Rule XXI, clause 2) prohibits any appropriation, whether in a reported appropriations bill or offered as an amendment, for an expenditure not authorized by law. The Senate (Rule XVI, paragraph 1) prohibits floor amendments proposing appropriations for an agency or activity not authorized by law, with certain exceptions. In contrast to the House, the Senate does not prohibit committee amendments or measures reported by the Appropriations Committee from including an appropriation for an agency or activity not authorized by law. Second, the House (Rule XXI, clause 2) and Senate (Rule XVI, paragraphs 2 and 4) prohibit the inclusion of legislative language (such as an authorization) in an appropriations measure. Third, the House (Rule XXI, clause 4), but not the Senate, prohibits appropriations in authorizing legislation.

So, although authorizing legislation is not strictly necessary, it's a lot harder to get an appropriation through the legislative process for an activity that has not been previously authorized.



Generally speaking, authorization is a power to granted to to an agency or department, and appropriation is the action that the agency or department takes. For instance, in H.R.3684 — from just a quick glance at the bill — we the see the repeated phrase "[X] is authorized to appropriate [some amount] from [Y]". This translates to a statement that Congress is allowing agency or department X to take funds from source Y to use for its ends.

Honestly, this isn't much more complicated than a parent saying to a child: "You have my permission to get $10 from the change jar in the kitchen so that you can go to the store to buy milk." The parent (congress) is certainly not going to get up off its lazy you-know-what to go buy milk — that job has been delegated to the child (agency) — but the child (agency) can't just grab money from wherever as it sees fit.

If you want a more detailed example, please give a specific clause of the bill that you'd like clarified..

  • 1
    First of all thanks for your answer! the common phrase in the bill is, as you mentioned: "there is authorized to be appropriated to X..." From my understanding, to stick to your example: This phrase allows the parents to give the child lets say $100 next year, without actually giving the child any money. When the parents do their budget in the next year, they dont have to appropriate $100 to the child, but they can (&will) if their budget allows such spending.
    – KDMS
    Oct 26, 2021 at 14:35
  • 1
    This does not answer the question.
    – markvs
    Oct 26, 2021 at 14:36
  • 2
    A specific example from the bill: In Sec. 22101: $12.65bn (over 5 years) are authorized to be appropriated to amtrak for the National Network. In the appropriation segment (Division J/page 2655): an additional amount of $16bn via advanced appropriations is granted to amtraks National Network. Is it those $16bn are guarenteed and $12.65bn might be added if appropriated in the future? Apta summarises this: apta.com/wp-content/uploads/… Are those $20bn authorizations "additional" and included in the $1tn bill-price?
    – KDMS
    Oct 26, 2021 at 14:45
  • @KDMS: there are no page numbers on the online version I'm looking at, FYI. At any rate, the only real difference I see (without really digging into the legalese) is that the first authorization is for the Secretary (I assume of transportation), while the later authorization is to the "National Railroad Passenger Corporation". I assume the first is for general infrastructure — things like bridge and track work — while the later is more railway specific (engines, railcars, depots and terminals, etc). That seems to hold with the subsequent itemized lists. Oct 26, 2021 at 16:04
  • @markvs: What is it missing? Oct 26, 2021 at 16:04

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .