---
type: "Bill"
title: "Special Mobile Machinery Registration Exemption"
description: "The act allows an owner of special mobile machinery who regularly rents or leases the special mobile machinery and who pays specific ownership tax on a monthly basis in an amount equal to 2% of the rental or lease payments for the special mobile machinery to apply to the department of revenue for a registration exempt certificate. The department shall issue the certificate if:The department verifies that the owner regularly has 1,000 or more items of such special mobile machinery in the state;"
jurisdiction: "us/states/co"
legislature: "Colorado General Assembly"
session: "2021A"
identifier: "SB 21-257"
citation: "Colorado SB 21-257 (2021A)"
classification: ["bill"]
subjects: []
status: "enacted"
primary_sponsors: ["Adrienne Benavidez", "Kevin Van Winkle", "Rachel Zenzinger", "Ray Scott"]
version_count: 8
action_count: 14
vote_count: 2
first_action: "2021-04-29T06:00:00+00:00"
last_action: "2021-07-07T06:00:00+00:00"
source: "openstates"
source_identifier: "ocd-bill/17315fd5-1ca4-44b5-aeef-7cee7ce04e2d"
source_url: "http://leg.colorado.gov/bills/sb21-257"
source_hash: "a0f0693525dce66ba1fa7c39362970c77ede5a1a154b4c7f8d012c9e0499d9ac"
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-co"]
---

# Colorado SB 21-257 (2021A) — Special Mobile Machinery Registration Exemption

The act allows an owner of special mobile machinery who regularly rents or leases the special mobile machinery and who pays specific ownership tax on a monthly basis in an amount equal to 2% of the rental or lease payments for the special mobile machinery to apply to the department of revenue for a registration exempt certificate. The department shall issue the certificate if:The department verifies that the owner regularly has 1,000 or more items of such special mobile machinery in the state;

## Version chain

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

1. **Committee Amendment** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/2021a_sb257_h_app_001.pdf)
2. **Engrossed (05/21/2021)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2021A/bills/2021a_257_eng.pdf)
3. **Final Act (06/17/2021)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2021A/bills/2021a_257_enr.pdf)
4. **Introduced (04/29/2021)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2021A/bills/2021a_257_01.pdf)
5. **Reengrossed (05/24/2021)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2021A/bills/2021a_257_ren.pdf)
6. **Rerevised (06/07/2021)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2021A/bills/2021a_257_rer.pdf)
7. **Revised (06/04/2021)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2021A/bills/2021a_257_rev.pdf)
8. **Signed Act (07/07/2021)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/2021a_257_signed.pdf)

## Votes

- BILL — **35–0** (pass) · upper
- BILL — **63–0** (pass) · lower

## Sponsors

- Adrienne Benavidez — primary (person)
- Kevin Van Winkle — primary (person)
- Rachel Zenzinger — primary (person)
- Ray Scott — primary (person)

## Timeline

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

- **2021-07-07T06:00:00+00:00** Governor Signed `executive-signature`
- **2021-06-17T06:00:00+00:00** Sent to the Governor `executive-receipt`
- **2021-06-17T06:00:00+00:00** Signed by the Speaker of the House
- **2021-06-17T06:00:00+00:00** Signed by the President of the Senate
- **2021-06-07T06:00:00+00:00** House Third Reading Passed - No Amendments `passage, reading-3`
- **2021-06-04T06:00:00+00:00** House Second Reading Special Order - Passed - No Amendments
- **2021-06-04T06:00:00+00:00** House Committee on Appropriations Refer Unamended to House Committee of the Whole `committee-passage, referral-committee`
- **2021-05-27T06:00:00+00:00** House Committee on Finance Refer Unamended to Appropriations `referral-committee`
- **2021-05-24T06:00:00+00:00** Introduced In House - Assigned to Finance `introduction`
- **2021-05-24T06:00:00+00:00** Senate Third Reading Passed - No Amendments `passage, reading-3`
- **2021-05-21T06:00:00+00:00** Senate Second Reading Special Order - Passed - No Amendments
- **2021-05-21T06:00:00+00:00** Senate Committee on Appropriations Refer Unamended to Senate Committee of the Whole `committee-passage, referral-committee`
- **2021-05-12T06:00:00+00:00** Senate Committee on Finance Refer Unamended to Appropriations `referral-committee`
- **2021-04-29T06:00:00+00:00** Introduced In Senate - Assigned to Finance `introduction`

## Source

OpenStates / OpenCivicData bulk snapshot [2026-07-01](https://data.openstates.org/daily/2026-07-01/public.pgdump); origin `ocd-bill/17315fd5-1ca4-44b5-aeef-7cee7ce04e2d`. Confidence: reported (aggregated from official Colorado legislature records).