Idaho charges $100 to form an LLC; Illinois charges $150. Day-one sticker price is only part of the story, since most of the real cost comes from the annual obligations that stack up each year you keep the LLC open.

Over a rolling three-year window, Idaho runs about $275 less in total state fees than Illinois. Whether that gap matters depends on whether you actually operate in one of these states or are weighing a non-resident filing.

On speed, Idaho typically clears standard online filings faster than Illinois. Both states offer expedited tiers at an additional cost for filers on tight timelines.

For most small operators the choice is not really between these two states at all. It is between forming where the business actually operates and trying to route through a non-resident filing. The data below shows what each option actually costs.

Formation filing fee
Idaho $100
Illinois $150
Idaho saves $50
Year 1 total estimate
Idaho $200
Illinois $325
Idaho saves $125
Ongoing per year
Idaho $100
Illinois $175
Idaho saves $75
3-year total
Idaho $400
Illinois $675
Idaho saves $275

Key differences at a glance

  • Idaho costs $50 less to form ($100 vs $150).
  • Idaho is $75 per year cheaper to maintain ($100 vs $175).

Where each state fits

For most filers, forming in the state you actually operate from is the right call. The side-by-side below shows where the two states meaningfully diverge.

Three-year cost, side by side

Rough estimate of the state-facing cost to form and keep an LLC through three years. Both totals include a $100 per year registered-agent estimate.

Idaho Illinois
Year 1
$200
$325
Year 2
$300
$500
Year 3
$400
$675

Running total includes the one-time filing fee and annual ongoing costs (report fee or franchise tax plus a $100/year registered agent estimate).

What it costs under your specific situation

The table below runs the same LLC through four common scenarios. "Non-resident" rows assume a typical home-state foreign LLC registration adds about $200 per year of stacked cost; the real number depends on which state you live in and ranges from $50 to over $800 depending on jurisdiction.

Scenario Year 1 Each year after 3-year total
You live in Idaho, business operates there
No foreign LLC registration needed. You pay Idaho fees only.
$200 $100 $400
You live in Illinois, business operates there
No foreign LLC registration needed. You pay Illinois fees only.
$325 $175 $675
Non-resident forming in Idaho with operations elsewhere
You pay Idaho's fees plus a typical home-state foreign LLC registration of about $200 per year.
$400 $300 $1,000
Non-resident forming in Illinois with operations elsewhere
You pay Illinois's fees plus a typical home-state foreign LLC registration of about $200 per year.
$525 $375 $1,275

Idaho vs Illinois: full comparison

Dimension Idaho Illinois
Online filing
Can you file the formation document online?
Yes Yes
Online approval time
Standard, non-expedited
7 business days 10 business days
Expedited option
Paid fast-track filing
$40 $100
Annual report
Required in addition to tax
Required, $0 Required, $75
State-imposed annual tax
Franchise, privilege, or LLC tax minimum
None None
State income tax
On pass-through LLC income at member level
Yes Yes
Publication requirement
Newspaper publication after formation
No No
Operating agreement
Required by state statute
Recommended, not required Recommended, not required
Foreign LLC fee
Cost to register as a foreign LLC in this state
$100 $150
State sales tax
General statewide rate
6.0% 6.3%

Taxes in Idaho and Illinois

How each state handles entity-level tax on LLCs. Pass-through classification means member-level income tax also applies at each member's residence state.

Idaho tax

No entity-level franchise tax on LLCs. State income tax applies to member-level pass-through income. Corporate rate 5.3%.

Illinois tax

No entity-level franchise tax on LLCs. State income tax applies to member-level pass-through income. Corporate rate 7.0%.

Ongoing compliance

The recurring filings each state requires after formation.

Idaho

Annual report $0, due on your anniversary month. Registered agent required in Idaho.

Illinois

Annual report $75, due on your anniversary month. Registered agent required in Illinois.

Formation process, side by side

What actually happens from the moment you start filing to the moment you're in good standing. Use this as a checklist.

Idaho

  1. Check business-name availability on the Idaho entity search.
  2. Appoint a registered agent with a physical Idaho street address.
  3. File Certificate of Organization Limited Liability Company for $100.
  4. Wait for approval. Online typically 7 business days. Paid expedite from $40.
  5. Adopt an operating agreement (recommended, not required by Idaho statute).
  6. Apply for a federal EIN (free from the IRS).
  7. Open a business bank account to separate personal and business finances.
  8. File your first annual report and pay $0 when it comes due.

Illinois

  1. Check business-name availability on the Illinois entity search.
  2. Appoint a registered agent with a physical Illinois street address.
  3. File Form LLC-5.5 - Articles of Organization for $150.
  4. Wait for approval. Online typically 10 business days. Paid expedite from $100.
  5. Adopt an operating agreement (recommended, not required by Illinois statute).
  6. Apply for a federal EIN (free from the IRS).
  7. Open a business bank account to separate personal and business finances.
  8. File your first annual report and pay $75 when it comes due.

Before you pick either state

A few things that apply no matter which state you choose. These trip up enough first-time filers that they're worth stating explicitly.

Registered agent is non-negotiable. Both Idaho and Illinois (and every other US state) require every LLC to designate a registered agent with a physical street address in the state of formation. You can serve as your own agent if you live in the state; otherwise a commercial agent runs $50 to $125 per year. Using your own home address makes it part of the public record.

Forming elsewhere does not escape your home state's tax. If you live and operate a business from your home state, forming the LLC in Idaho or Illinois does not avoid your home state's income tax. The moment you transact business at home, your home state requires a foreign LLC registration, and state tax liability follows your residence regardless of where the entity sits on paper.

EIN applications are free. The IRS issues Employer Identification Numbers directly at no cost. Any service charging you to "get your EIN" is reselling a free form submission. Single-member LLCs with no employees technically don't need one for federal tax, but nearly every bank requires an EIN to open a business account.

Operating agreement matters more than the state you pick. A well-drafted operating agreement governs member ownership, management, profit splits, buy-sell terms, and dissolution. Without one, your LLC runs on the state's default rules, which are rarely what you want. California, Maine, Missouri, and New York require a written one by statute; every other state treats it as strongly recommended.

Agency contacts

Idaho Secretary of State - Business Services Division

Website
sos.idaho.gov
Phone
(208) 334-2301
Mail
Office of the Secretary of State, 450 N 4th Street, PO Box 83720, Boise, ID 83720-0080
Office
450 N 4th Street, Boise, ID 83702
Hours
8:00 AM to 5:00 PM Mountain, Monday to Friday

Illinois Secretary of State, Department of Business Services

Website
www.ilsos.gov/departments/business_services/home.html
Phone
(217) 524-8008
Mail
Limited Liability Division, 501 S. Second St., Room 351, Springfield, IL 62756
Office
501 S. Second St., Room 351, Springfield, IL 62756
Hours
8:00 AM to 4:30 PM Central, Monday to Friday

Idaho State Tax Commission

Website
tax.idaho.gov
Phone
(208) 334-7660
Mail
Idaho State Tax Commission, PO Box 36, Boise, ID 83722-0410
Office
11321 W Chinden Blvd, Building 2, Boise, ID 83714
Hours
8:00 AM to 5:00 PM Mountain, Monday to Friday

Illinois Department of Revenue

Website
tax.illinois.gov
Phone
(800) 732-8866
Mail
101 West Jefferson Street, Springfield, IL 62702
Office
555 West Monroe, Suite 1100, Chicago, IL 60661
Hours
8:30 AM to 5:00 PM Central, Monday to Friday

Frequently Asked Questions

  • Is it cheaper to form an LLC in Idaho or Illinois?

    Idaho is cheaper at formation ($100) than Illinois ($150). Ongoing costs are also different: $100 vs $175 per year. Total over three years: $400 vs $675.

  • Can I form an LLC in Idaho if I live in Illinois?

    Yes, but your Illinois business will almost certainly need to register as a foreign LLC in Illinois too, which means paying Illinois's foreign registration fee and any ongoing Illinois obligations on top of the Idaho ones. The "form elsewhere to save" math usually doesn't work for operating businesses; it only works when you have no physical operations tied to any specific state.

  • How long does it take to form an LLC in Idaho vs Illinois?

    Idaho online: 7 business days; Illinois online: 10 business days. Idaho offers paid expedite from $40. Illinois offers paid expedite from $100.

  • Which state has lower taxes for an LLC, Idaho or Illinois?

    Idaho: state income tax applies to member-level pass-through income, no entity-level franchise or LLC tax. Illinois: state income tax applies to member-level pass-through income, no entity-level franchise or LLC tax.

  • Do both states require a registered agent?

    Yes. Every US state (and DC) requires every LLC to maintain a registered agent with a physical street address in the state. Idaho and Illinois both have this requirement. You can serve as your own agent if you live in the state; most out-of-state filers use a commercial agent for $50 to $125 per year.

  • Which state should I pick if I run an online business from home?

    Form in the state you actually live in. Your home state's Department of Revenue treats your residence as nexus regardless of where the LLC is filed, which means you owe state income tax there anyway. Forming in Idaho or Illinois to escape your home state's tax doesn't work; it adds paperwork. The non-resident filings make sense when you genuinely operate nowhere in particular: international founders, purely passive holding entities, or real-estate LLCs owning property in other states.

Full state guides

More Idaho and Illinois comparisons

Sources

  • Filing fee: sos.idaho.gov/CORP/forms/LLC/LLC%20Cert%20org.pdf · verified April 21, 2026
    Idaho SoS Certificate of Organization Limited Liability Company form (Title 30, Chapters 21 and 25, Idaho Code): base filing fee is $100.00. Paper filings add a $20.00 manual processing fee, bringing the paper total to $120.00. Online filings through SOSBiz are the $100 base rate.
  • Expedited filing: sos.idaho.gov/CORP/forms/LLC/LLC%20Cert%20org.pdf · verified April 21, 2026
    Certificate of Organization instructions: expedited service adds $40.00 (8-hour); same-day service adds $100.00. Recording the cheapest expedited tier (8-hour, $40) as the default expedited fee.
  • Foreign LLC registration fee: sos.idaho.gov/business-forms/ · verified April 21, 2026
    Foreign LLC Foreign Registration Statement base filing fee is $100.00 online through SOSBiz; paper filings add the $20 manual processing fee for a $120 paper total.
  • Operating agreement requirement: legislature.idaho.gov/statutesrules/idstat/Title30/T30CH25/ · verified April 21, 2026
    Idaho Uniform Limited Liability Company Act, Idaho Code Title 30, Chapter 25, does not require a written operating agreement. The Certificate of Organization instructions explicitly state: 'Please do not attach operating agreements. They are not filed with this office.' (Idaho Code Section 30-25-201(C)).
  • Publication requirement: sos.idaho.gov/business-forms/ · verified April 21, 2026
    Idaho Uniform LLC Act and SoS filing instructions contain no publication requirement for LLCs.
  • Annual report fee: sos.idaho.gov/annual-report-help/ · verified April 21, 2026
    Idaho annual report filing fee is $0 for online filing through SOSBiz. Paper annual report filings incur the $20 manual processing fee. Due by the end of the anniversary month; administrative dissolution follows 60 days of non-filing.
  • Franchise tax: tax.idaho.gov/ · verified April 21, 2026
    Idaho State Tax Commission imposes no franchise tax on LLCs. C-corps (including LLCs electing C-corp treatment) pay the 5.3% corporate income tax with a $20 minimum; this is an income tax, not a franchise tax.
  • Corporate income tax rate: tax.idaho.gov/pressrelease/whats-new-for-2025-income-tax-returns/ · verified April 21, 2026
    Idaho corporate income tax rate reduced to 5.3% (flat) effective retroactive to January 1, 2025, per House Bill signed in 2025. Previous rate was 5.695%. The 5.3% rate continues in 2026. Corporate minimum tax is $20. Idaho individual rate is also a flat 5.3%.
  • Sales tax rate: tax.idaho.gov/taxes/sales-use/ · verified April 21, 2026
    Idaho statewide sales and use tax rate is 6.0%. A small number of resort cities may impose local option sales taxes, but there is no general local sales tax.
  • Business name search: sosbiz.idaho.gov/search/business · verified April 21, 2026
    Idaho SOSBiz business entity search. Confirm name availability before filing Certificate of Organization (Idaho Code Section 30-21-301 governs LLC name requirements).
  • Online filing portal: sosbiz.idaho.gov/ · verified April 21, 2026
    Idaho SOSBiz is the online business filing portal. Requires free account. Online filings bypass the $20 manual processing fee that applies to paper submissions.
  • Filing fee: law.justia.com/codes/illinois/chapter-805/act-805-ilcs-180/article-50/… · verified April 21, 2026
    805 ILCS 180/50-10(b)(1): 'Filing articles of organization (domestic), application for admission (foreign), and restated articles of organization (domestic), $150.' Series LLC formation fee is $400 under the same subsection.
  • Expedited filing: law.justia.com/codes/illinois/chapter-805/act-805-ilcs-180/article-50/… · verified April 21, 2026
    805 ILCS 180/50-50(e): Expedited fees include Articles of Organization $100, Articles of Amendment $100, Reinstatement $100, Application for Admission $100, Merger $200, Restated Articles $200. 24-hour turnaround for most expedited services.
  • Online filing portal: apps.ilsos.gov/llcarticles/index.jsp · verified April 21, 2026
    Illinois Secretary of State online Articles of Organization filing portal.
  • Certificate of Formation form: www.ilsos.gov/publications/business-services/llc.html · verified April 21, 2026
    Form LLC-5.5 Articles of Organization. PDF hosted at https://www.ilsos.gov/publications/pdf_publications/llc55.pdf
  • Business name search: apps.ilsos.gov/corporatellc/ · verified April 21, 2026
    Illinois Secretary of State business entity search.
  • Operating agreement requirement: law.justia.com/codes/illinois/chapter-805/act-805-ilcs-180/article-1/ · verified April 21, 2026
    805 ILCS 180/1-5 defines 'operating agreement' as an agreement 'whether oral, in a record, implied, or in any combination thereof.' No statutory requirement for a written operating agreement.
  • Publication requirement: law.justia.com/codes/illinois/chapter-805/act-805-ilcs-180/ · verified April 21, 2026
    805 ILCS 180 imposes no newspaper publication requirement for LLC formation.
  • Foreign LLC registration fee: law.justia.com/codes/illinois/chapter-805/act-805-ilcs-180/article-50/… · verified April 21, 2026
    805 ILCS 180/50-10(b)(1): Application for Admission (foreign LLC) fee is $150, same as domestic Articles of Organization.
  • Annual report fee: law.justia.com/codes/illinois/chapter-805/act-805-ilcs-180/article-50/… · verified April 21, 2026
    805 ILCS 180/50-10(b)(11): Annual report fee $75, plus $50 per series for series LLCs. 805 ILCS 180/50-15(b)(1) penalty: $100 plus $100 for each year of delinquency. Deadline is before the first day of the anniversary month (§50-1(b)).
  • Franchise tax: tax.illinois.gov/research/taxrates/income.html · verified April 21, 2026
    Illinois phased out the corporate franchise tax effective January 1, 2024 (P.A. 102-16). LLCs classified as partnerships pay Personal Property Replacement Tax at 1.5% of net income, but this is not classified as a franchise tax. No franchise tax applies to LLCs.
  • Corporate income tax rate: tax.illinois.gov/research/taxrates/income.html · verified April 21, 2026
    Illinois corporate income tax is 7% of net income, plus 2.5% Personal Property Replacement Tax, for a combined 9.5% rate on C-corporation income. Individual income tax is 4.95% (flat).
  • Sales tax rate: tax.illinois.gov/questionsandanswers/answer.139.html · verified April 21, 2026
    Illinois state general merchandise sales tax rate is 6.25%. Effective January 1, 2026, the 1% state grocery tax was eliminated. Local jurisdictions may impose additional taxes; combined rates vary by location.