Southern Insurance Underwriters (SIU) is a family-owned certified Managing General Agency (MGA) based in Alpharetta, Georgia, founded in 1964. It is not a retail insurance company, so consumers don’t buy policies directly from it. Instead, SIU acts as a wholesaler, giving over 2,500 independent agents across the Southeast access to more than 120 markets and 150-plus specialty carriers, including Lloyd’s of London. It specializes in hard-to-place, specialty, and excess and surplus lines risks. You can reach SIU at +1 678-498-4500, and its headquarters is at 4500 Mansell Road, Alpharetta, GA 30022.
Southern Insurance Underwriters: Key Facts at a Glance
| Detail | Information |
|---|---|
| Company type | Certified Managing General Agency (MGA), wholesaler |
| Founded | July 1, 1964 |
| Headquarters | 4500 Mansell Road, Alpharetta, GA 30022 |
| Phone | +1 678-498-4500 |
| Serves | Over 2,500 independent agents |
| States | Alabama, Florida, Georgia, Mississippi, South Carolina, Tennessee |
| Markets and carriers | 120-plus markets, 150-plus carriers plus Lloyd’s |
| Ownership | Family-owned (Duesenberg family) |
Southern Insurance Underwriters is one of the largest family-owned MGAs in the country, and it has served independent agents in the Southeast for over 60 years. The most important thing to understand is what it is not: it isn’t a company you call to buy car or home insurance. It’s the wholesaler behind the scenes that agents use to place tough risks. This profile explains what SIU does, who owns it, how to reach it, and clears up the confusion its name creates.
What Is Southern Insurance Underwriters?
SIU is a certified Managing General Agency, often shortened to MGA. An MGA sits between insurance carriers and the local independent agents who work with the public. Carriers give the MGA authority to underwrite and place certain kinds of risks. In turn, the MGA gives agents access to markets they couldn’t reach on their own.
In plain terms, SIU is a wholesaler. A consumer or business owner does not buy a policy from SIU directly.
Here’s how a risk actually flows. Say a trucking company can’t find coverage through standard insurers. Its local independent agent brings that risk to SIU. SIU then shops it across the specialty carriers and Lloyd’s syndicates it represents, finds a market, and helps place the policy. The trucking company still deals with its own agent. SIU works one layer back, as the market-maker. That’s why searching for “Southern Insurance Underwriters” to get a personal quote leads nowhere useful. The right path for a consumer is simply to work with an independent agent, who may then use SIU behind the scenes.
Who Owns Southern Insurance Underwriters? A History Since 1964
SIU is a family-owned business, and its story starts on July 1, 1964. On that date, W.C. Duesenberg, Sr. purchased the Atlanta branch office of Kurt Hitke and Company and created Southern Insurance Underwriters, Inc. The company has stayed in the Duesenberg family ever since. That kind of continuity is unusual for an MGA of its size.
In its early years, SIU focused on Non-Standard Auto coverage. It also wrote specialty lines like Commercial Trucking and coverage for senior drivers. Over the decades it broadened well beyond that.
Today its lineup spans Commercial Property and Casualty, Commercial Transportation, Personal Property, Professional Lines, and Standard Lines. The through-line across 60-plus years has been specializing in risks other insurers find hard to place. That focus on the hard cases is what built its reputation. When a standard market says no, a wholesaler like SIU is where an agent turns next.
What SIU Offers: Lines, Markets, and Carriers
Because SIU is a wholesaler, its “products” are really access. It gives agents a wide shelf of markets and carriers to solve problems that standard insurers decline.
SIU provides access to more than 120 markets. It represents over 150 admitted and non-admitted specialty companies, plus Lloyd’s of London and several standard carriers. Its focus is hard-to-place, specialty, and excess and surplus lines, meaning the unusual or higher-risk accounts that need a specialist. The scope runs from a simple property risk to a highly complex self-insured program. Few standard insurers try to cover that range. SIU also owns an affiliated premium finance company, SIUPREM. It helps agents and their clients spread premium payments over time. For a business facing a large specialty premium, that financing can make the coverage affordable. It’s a practical add-on that many standalone carriers don’t offer. The kinds of accounts SIU handles show its specialty focus. Think artisan contractors, electricians, carpenters, janitorial and lawn-care businesses, trucking fleets, and non-standard auto. These are risks that standard carriers often decline or price out of reach. For an independent agent, the appeal is one wholesaler that can quote a janitorial contractor, a trucking fleet, or a professional liability account, all from a single relationship. That breadth is what keeps agents coming back to an MGA rather than chasing individual carriers one by one.
Southern Insurance Underwriters Contact: Phone, Address, and Locations
If you need to reach SIU, here are the verified details. The main phone number is +1 678-498-4500, and the headquarters is at 4500 Mansell Road, Alpharetta, Georgia 30022. The company is often associated with Atlanta. Alpharetta sits in the metro Atlanta area, and SIU began as an Atlanta branch office.
Beyond the Alpharetta headquarters, SIU operates a branch office in Lake Mary, Florida, which supports its agents in the Florida market. Keep in mind who those lines are built for. As a wholesaler, SIU’s phones and portals serve its independent agents, not the general public seeking a personal quote. If you’re a consumer, your own agent is the right first call.
Agent Login and How Agents Work With SIU
The Southern Insurance Underwriters agent login is a portal for appointed independent agents, not a public account. Through it, agents can quote online using SIU’s raters for commercial, personal, and standard lines, and manage their business with the MGA.
To use it, an agent generally needs to be appointed with SIU. The company has long treated technology as a differentiator, with online quoting tools for agents. In July 2025 it went a step further. It adopted an AI automation platform to speed up how submissions are handled. For an agent, the practical benefit is faster quotes across many markets from a single login. For a consumer, the login isn’t relevant, since you don’t hold an account with an MGA.
Southern Insurance Underwriters Reviews: What’s Actually Out There
Here’s an honest note on reviews, because it matters. SIU is a wholesaler, not a retail insurer, so it doesn’t collect consumer star ratings the way a company like State Farm or Progressive does. Most people who deal with SIU are agents and carriers, not policyholders, so public consumer reviews are limited and not very meaningful.
Where you will find feedback is on employer and business platforms, where agents and staff comment on working with or for the company. Treat any specific satisfaction percentages you see online with caution, since many are unsourced. The fairer way to judge an MGA is by its carrier relationships, its longevity, and its standing with agents, and on those measures SIU’s 60-plus years and 2,500-plus appointed agents speak for themselves. If you’re an agent weighing SIU, ask peers in your state about service and turnaround rather than trusting a single rating.
Careers and Industry Standing
SIU offers careers in insurance underwriting, marketing, and support roles at its Georgia and Florida offices, and it presents itself as a long-tenured, family-owned employer. Rather than repeat unverified salary figures floating online, the honest summary is that roles center on the underwriting and agency-service work an MGA runs on.
The company is active in the major industry bodies, including the Wholesale and Specialty Insurance Association, which absorbed the former AAMGA and NAPSLO, along with the Professional Insurance Agents and the Big I independent-agent associations across its states. That involvement is a reasonable signal of an established, mainstream MGA. The company also supports local charities across its region, from healthcare foundations to youth sports. None of that guarantees good service on a given account, but it does mark SIU as a rooted, long-term operator rather than a fly-by-night wholesaler.
Clearing Up the Confusion: The Company vs. the Job vs. an SIU Investigation
The name “Southern Insurance Underwriters” collides with a few unrelated things in search results, so let’s separate them.
First, the company. That’s SIU the Georgia MGA, the subject of this page. Second, the job. An insurance underwriter is a person who evaluates risk and decides whether and how to cover it, and at what price. An underwriter is a role or a person, not an insurance company, though carriers and MGAs like SIU employ them. Third, and most confusing, is a different “SIU” entirely: a Special Investigations Unit, which is an insurance fraud investigation team. So a search like “how long does an SIU investigation take” is about fraud units, not this company. And “Big 4 title underwriters” refers to the largest title insurance underwriters, a separate corner of insurance. If your question is about the Georgia MGA, this page is the right one.
Is SIU Relevant to You?
A quick way to know where you stand. If you’re a consumer or business owner looking for a policy, SIU is not who you call, because you buy through an independent agent, who may use SIU as one of their markets. If you’re an independent agent with a hard-to-place risk, SIU is exactly the kind of wholesaler you’d approach. An appointment gives you access to its specialty markets and its underwriters. That can be the difference between placing a tough account and losing the client. And if you landed here from a fraud-investigation or title-insurance search, you’re likely looking for a different “SIU” or “underwriter” altogether. Match your situation to one of those, and the next step is clear.
The Honest Read
Southern Insurance Underwriters is a solid, established MGA, and the honest takeaway depends entirely on who you are. For an independent agent in the Southeast, SIU is a credible, long-running wholesaler with deep specialty and excess and surplus market access, worth an appointment if you place hard risks. For a consumer, the key insight is simply that you can’t and don’t buy from SIU directly, so the brand searches that lead here are usually a detour. The company’s real value is the market access it gives agents, not a retail product. Judge it as what it is, a wholesaler, and it holds up well. The mismatch only appears when a consumer expects a storefront and finds a market-maker instead.
Conclusion
Southern Insurance Underwriters is a family-owned certified MGA in Alpharetta, Georgia, founded in 1964, serving over 2,500 independent agents across the Southeast with access to more than 120 markets and 150-plus carriers, including Lloyd’s. It specializes in hard-to-place and excess and surplus lines, not retail policies you buy directly. Reach it at +1 678-498-4500 or 4500 Mansell Road, Alpharetta, GA 30022. If you’re an agent, it’s a market worth knowing. If you’re a consumer, your independent agent is the bridge to what SIU offers.
FAQs
What are Southern Insurance Underwriters?
Southern Insurance Underwriters, Inc. (SIU) is a family-owned certified Managing General Agency based in Alpharetta, Georgia, founded in 1964. It’s a wholesaler that gives independent agents access to specialty and excess and surplus insurance markets. It is not a retail insurer that sells policies directly to the public.
Who owns Southern Insurance Underwriters?
SIU is family-owned and has been since W.C. Duesenberg, Sr. founded it on July 1, 1964, after buying the Atlanta branch of Kurt Hitke and Company. It remains one of the largest family-owned MGAs in the country. That continuity is unusual for an agency of its size.
What is the Southern Insurance Underwriters phone number?
The main phone number for Southern Insurance Underwriters is +1 678-498-4500. The number primarily serves the independent agents SIU works with, rather than the general public. Confirm current contact details on the company’s official site, since they can change.
Where is Southern Insurance Underwriters located?
SIU is headquartered at 4500 Mansell Road, Alpharetta, Georgia 30022, in the metro Atlanta area. It also operates a branch office in Lake Mary, Florida. The company serves agents across the southeastern United States from these locations.
Is Southern Insurance Underwriters an insurance company?
Not in the usual sense. SIU is a Managing General Agency, or wholesaler, not a carrier that issues and backs its own policies. It connects independent agents to carriers and Lloyd’s of London markets. The actual insurance is underwritten by the carriers SIU represents.
Can I buy insurance directly from Southern Insurance Underwriters?
No. As a wholesale MGA, SIU works through independent agents rather than selling to the public. To access the markets SIU offers, you work with a local independent agent, who can place your risk through SIU if it fits. Consumers don’t hold accounts with SIU.
What does Southern Insurance Underwriters offer?
SIU offers agents access to Commercial Property and Casualty, Commercial Transportation, Personal Property, Professional Lines, and Standard Lines. It specializes in hard-to-place, specialty, and excess and surplus risks. It also runs an affiliated premium finance company, SIUPREM.
How do I access the SIU agent login?
The agent login is a portal for appointed independent agents, not the public. Agents use it to quote and manage business across SIU’s markets. To get access, an agent typically needs an appointment with SIU, arranged through the company.
Are there reviews of Southern Insurance Underwriters?
Because SIU is a wholesaler rather than a retail insurer, public consumer reviews are limited and not very meaningful. Most feedback comes from agents and employees on business and employer platforms. Be cautious with any specific satisfaction percentages online, as many are unsourced.
What is an insurance underwriter?
An insurance underwriter is a person who evaluates a risk and decides whether to insure it, on what terms, and at what price. It’s a role, not a company. Carriers and MGAs like SIU employ underwriters to assess applications and set coverage.
Is an underwriter the same as an insurance company?
No. An underwriter is a person or role that assesses and prices risk, while an insurance company is the business that issues and backs the policy. A single insurer or MGA employs many underwriters. The two terms are related but not interchangeable.
How long does an SIU investigation take?
That question refers to a different “SIU,” a Special Investigations Unit that investigates suspected insurance fraud, not Southern Insurance Underwriters the MGA. Fraud investigation timelines vary widely by case and insurer. This page is about the Georgia company, not fraud units.
Who are the Big 4 title underwriters?
This refers to title insurance, a separate field from Southern Insurance Underwriters. The largest title insurance underwriters are generally First American, Fidelity National, Old Republic, and Stewart. They are unrelated to the Georgia MGA discussed here.
Does Southern Insurance Underwriters handle claims?
Claims are ultimately handled by the carrier that underwrote the policy, not by the MGA itself, though SIU and the agent help coordinate. Because policies are placed through independent agents, a policyholder usually starts a claim with their agent or the carrier named on the policy.
What states does Southern Insurance Underwriters serve?
SIU primarily serves independent agents in Alabama, Florida, Georgia, Mississippi, South Carolina, and Tennessee. Its headquarters is in Alpharetta, Georgia, with a branch in Lake Mary, Florida. Its focus is the southeastern United States.
About This Profile
The InsuranceGuidances Editorial Team researches insurance companies and industry entities using primary sources. This profile drew on Southern Insurance Underwriters’ official website and About page, its LinkedIn and Crunchbase listings, industry directories, and a 2025 company announcement. It is independent and not affiliated with SIU. Reviewed July 2026.
Sources
Wholesale and Specialty Insurance Association (WSIA), successor to AAMGA and NAPSLO (wsia.org)
Southern Insurance Underwriters, official website and homepage (site.siuins.com)
Southern Insurance Underwriters, “About Us” company history and lines (siuins.com)
Crunchbase, Southern Insurance Underwriters company profile and founding (crunchbase.com)
LinkedIn, Southern Insurance Underwriters, Inc. company page (linkedin.com)
ZoomInfo, Southern Insurance Underwriters overview and markets (zoominfo.com)
MyNewMarkets.com, SIU company profile and headquarters address (mynewmarkets.com)
CB Insights, Southern Insurance Underwriters headquarters and phone (cbinsights.com)
SIUPREM, Inc., affiliated premium finance company (siuprem.com)
Expert Insured / PR Newswire, July 2025 SIU AI automation announcement (prnewswire.com)
