LLC Review Desk's 2026 picks for registered agents in Colorado, favorite first, are Mainstay Filing ($149 a year), CO Registered Agent.org ($99 a year) and Colorado Registered Agent.co ($99 a year). Mainstay Filing is our favorite, because you pay $149 a year whether you stay in one state or grow, and your first three government letters each year are scanned free.
By the LLC Review Desk editorial team
Position 1
Our top pick
1. Mainstay Filing: best for all fifty states
$149 a year, the same each year
Our score
9.2out of 10
9.2 out of 10
Our favorite is Mainstay Filing, because it's $149 a year and the price doesn't climb at renewal, plus papers served on the company get scanned the same business day for free.
Starting from scratch? The $199 yearly package adds the Colorado filing and the periodic report.
Over three years it costs $150 more than CO Registered Agent.org, and for us the extra things it handles are worth that.
In the price
An in-state street address as your registered office
Legal papers served on the company are scanned within the business day at no cost
Three government letters a year scanned at no cost to you
Compliance reminders
What we like
Your first three government letters each year, scanned for free
Fine for LLCs, corporations, LPs, LLPs and nonprofits
Same-business-day scans of papers served on the company, no charge
$149 a year and it stays flat
Trade-offs
The agent plan alone is $50 a year more than CO Registered Agent.org
3. Colorado Registered Agent.co: best for Colorado specialists
$99 a year, the same each year
Our score
8.7out of 10
8.7 out of 10
In third place is Colorado Registered Agent.co, because it's $99 a year, and the price stays put at renewal, the smallest yearly price among these picks.
Colorado Registered Agent.co takes care of the registered office with a street address in the state and scans everything served there.
CO Registered Agent.org and Colorado Registered Agent.co share a price and a feature list, so you can't go wrong with either.
In the price
An in-state address on the public record
Anything served on the company is scanned for you to open online
What we like
A lower yearly price than Mainstay Filing
$99 yearly, no change at renewal
LLC formation with year-one agent service included
Trade-offs
The periodic report is a job that stays with you
Built for Colorado; other states need another agent
Our scores out of 10 are editorial: LLC Review Desk sets them using the criteria on How we rank. They aren't customer ratings.
What Colorado registered agents cost in 2026: year one, renewals and three years
Service
First year
Second year
Third year
Three-year total
Same price when you renew
Mainstay Filing
$149
$149
$149
$447
Yes
CO Registered Agent.org
$99
$99
$99
$297
Yes
Colorado Registered Agent.co
$99
$99
$99
$297
Yes
We took each price from the company's own pages on November 12, 2026. Colorado's own fees stay the same no matter which agent you choose.
How we scored these
Two things count most to us, three-year cost and filings in the price, at 29% each. Renewal price, state fit and up-front totals share 42%, and Colorado came down to filings in the price.
Mainstay's plan does more: it scans papers served on the company the same business day, free, and the price is the same in all fifty states, with three government letters a year scanned at no charge. CO Registered Agent.org costs less, so it's a close race.
You can read every criterion and weight on How we rank.
What Colorado says about the registered agent (via Colorado Secretary of State)
Every LLC must name a registered agent with an in-state street address. The address has to be a physical address in Colorado, either a home or a usual place of business. P.O. boxes are not accepted. The law: C.R.S. § 7-90-701.
The Colorado periodic report: when and how much
Here's the schedule: the periodic report is due every year in Colorado, by last day of the entity's anniversary month. It costs $25. If you're late, add $50. Reminders from the state go to your registered agent.
Your questions about Colorado registered agents
Do I really need a registered agent for a Colorado LLC?
You do. Colorado won't accept an LLC without a registered agent who has a street address in the state, and that name goes on the public record.
What do Colorado registered agents usually cost per year?
Plan on $99 to $149 a year, and each service keeps its price when you renew.
Can I be my own registered agent?
Sometimes, if you meet the state's rules. A person 18 or older whose home or usual place of business is in Colorado (since July 1, 2025 the person has to hold a Colorado driver's license or ID or otherwise verify residency), or a business entity in good standing with a usual place of business in Colorado. The agent has to consent.
When do I have to send in the Colorado periodic report?
Mark last day of the entity's anniversary month on your calendar. The state's charge is $25, and sending it late tacks on $50.
Which registered agents did we review here?
Mainstay Filing ($149 a year), CO Registered Agent.org ($99 a year) and Colorado Registered Agent.co ($99 a year), with our favorite first.
Who is the best registered agent for Colorado?
Mainstay Filing, because one plan, $149 a year, follows the company to any state and renews at $149.