---
type: "Bill"
title: "Income tax; interest accrual and due dates of certain reports or returns; emergency declaration; modifying period of underpayment for corporations. Effective date. Emergency."
description: "Income tax; interest accrual and due dates of certain reports or returns; emergency declaration; modifying period of underpayment for corporations. Effective date. Emergency."
jurisdiction: "us/states/ok"
legislature: "Oklahoma Legislature"
session: "2021"
identifier: "SB 601"
citation: "Oklahoma SB 601 (2021)"
classification: ["bill"]
subjects: []
status: "enacted"
primary_sponsors: ["Pfeiffer", "Rader"]
version_count: 9
action_count: 27
vote_count: 0
first_action: "2021-02-01"
last_action: "2021-05-07"
source: "openstates"
source_identifier: "ocd-bill/5914e591-bfdf-4be4-895d-d22149cd9b7f"
source_url: "http://www.oklegislature.gov/BillInfo.aspx?Bill=SB601&session=2100"
source_hash: "29a784ef5d1edee8833a28ee4d391f5ce9315e274f6f361d2863583d62e04e77"
vintage: "2026-07-01"
source_snapshot: "https://data.openstates.org/daily/2026-07-01/public.pgdump"
retrieved_at: "2026-07-06"
confidence: "reported"
tags: ["legislation", "bill", "us-ok"]
---

# Oklahoma SB 601 (2021) — Income tax; interest accrual and due dates of certain reports or returns; emergency declaration; modifying period of underpayment for corporations. Effective date. Emergency.

## Version chain

The bill's text revisions, in order — the diff chain from filing to enrollment.

1. **Introduced** (filed) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 INT/SB/SB601 INT.PDF)
2. **Amended And Engrossed** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 AMENDMENTS/Amendment & Engr/SB601 HASB & ENGR.PDF)
3. **Engrossed** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 ENGR/SB/SB601 ENGR.PDF)
4. **Enrolled (final version)** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 ENR/SB/SB601 ENR.PDF)
5. **Floor (House)** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 FLR/HFLR/SB601 HFLR.PDF)
6. **Floor (Senate)** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 FLR/SFLR/SB601 SFLR.PDF)
7. **House Committee Substitute for Senate Bill** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 COMMITTEE SUBS/HCSS/SB601 HCS.PDF)
8. **SB601 SUBPCS1 JOHN PFEIFFER-MAH.PDF** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 COMMITTEE AMENDMENTS/House/SB601 SUBPCS1 JOHN PFEIFFER-MAH.PDF)
9. **Sub Committee Recommendation** (committee substitute) — [source](http://webserver1.lsb.state.ok.us/cf_pdf/2021-22 COMMITTEE SUBS/HCSS/SB601 SUBREC.PDF)

## Sponsors

- Pfeiffer — primary (person)
- Rader — primary (person)

## Timeline

The legislative action history — every referral, reading, and vote.

- **2021-02-01** First Reading `introduction, reading-1`
- **2021-02-01** Authored by Senator Rader
- **2021-02-02** Second Reading referred to Finance `reading-2, referral-committee`
- **2021-02-02** Reported Do Pass Finance committee; CR filed `committee-passage`
- **2021-02-09** Coauthored by Representative Pfeiffer (principal House author)
- **2021-02-11** General Order, Considered
- **2021-02-11** Measure passed: Ayes: 47 Nays: 0 `passage`
- **2021-02-11** Referred for engrossment
- **2021-02-18** Engrossed to House `passage`
- **2021-02-18** First Reading `introduction, reading-1`
- **2021-03-22** Second Reading referred to Appropriations and Budget `reading-2, referral-committee`
- **2021-03-23** Referred to Appropriations and Budget Finance - Revenue and Taxation Subcommittee `referral-committee`
- **2021-03-30** Recommendation to the full committee; Do Pass, amended by committee substitute Appropriations and Budget Finance - Revenue and Taxation Subcommittee `committee-passage`
- **2021-04-15** CR; Do Pass, amended by committee substitute Appropriations and Budget Committee `committee-passage`
- **2021-04-15** Emergency added
- **2021-04-22** General Order
- **2021-04-22** Third Reading, Measure and Emergency passed: Ayes: 93 Nays: 0 `passage, reading-3`
- **2021-04-22** Referred for engrossment
- **2021-04-26** Engrossed, signed, to Senate `passage`
- **2021-04-26** HAs read
- **2021-04-29** HAs adopted
- **2021-04-29** Measure and Emergency passed: Ayes: 42 Nays: 3 `passage`
- **2021-04-29** Referred for enrollment
- **2021-05-03** Enrolled, to House
- **2021-05-03** Signed, returned to Senate
- **2021-05-03** Sent to Governor `executive-receipt`
- **2021-05-07** Approved by Governor 05/07/2021 `executive-signature`

## Source

OpenStates / OpenCivicData bulk snapshot [2026-07-01](https://data.openstates.org/daily/2026-07-01/public.pgdump); origin `ocd-bill/5914e591-bfdf-4be4-895d-d22149cd9b7f`. Confidence: reported (aggregated from official Oklahoma legislature records).