THIS IS NEITHER AN OFFER TO SELL NOR A SOLICITATION OF AN OFFER TO BUY THE SECURITIES DESCRIBED HEREIN. THE OFFERING IS MADE ONLY BY THE PROSPECTUS. THIS MATERIAL MUST BE READ IN CONJUNCTION WITH THE PROSPECTUS IN ORDER TO UNDERSTAND FULLY ALL OF THE IMPLICATIONS AND RISKS OF THE OFFERING OF SECURITIES TO WHICH IT RELATES. A COPY OF THE PROSPECTUS MUST BE MADE AVAILABLE TO YOU IN CONNECTION WITH THE OFFERING DESCRIBED HEREIN. NO OFFERING IS MADE EXCEPT BY A PROSPECTUS FILED WITH THE DEPARTMENT OF LAW OF THE STATE OF NEW YORK. NEITHER THE ATTORNEY GENERAL OF THE STATE OF NEW YORK NOR ANY OTHER STATE REGULATORS HAVE PASSED ON OR ENDORSED THE MERITS OF THIS OFFERING. ANY REPRESENTATION TO THE CONTRARY IS UNLAWFUL.

THE RIGHT SECTORTHE RIGHT STRATEGYTHE RIGHT SPONSOR

Housing America’s GenerationALL® Renters:Millennials through Baby Boomers

SUMMARY RISK FACTORS

An investment in Steadfast Apartment REIT III involves a high degree of risk. You should purchase shares only if you can afford a loss of some or all of your investment. You should carefully consider the information set forth in the “Risk Factors” section of the prospectus for a discussion of material risk factors relevant to an investment in our common stock, including, but not limited to, the following:

• We have a limited prior operating history; there is no assurance that we will successfully achieve our investment objectives.

• There is no public market for our shares and we are not obligated to effectuate a liquidity event by a certain date or at all. It will be difficult for you to sell your shares of common stock. If you are able to sell your shares, you will likely sell them at a substantial discount.

• This is a “blind pool” offering. You will not have the opportunity to evaluate our investments before we make them.

• You are limited in your ability to have all or any portion of your shares of our common stock repurchased under our share repurchase program, and, if you are able to have your shares repurchased, you may receive less than the price you paid for the shares and the then-current value of the shares.

• The repurchase of shares pursuant to our share repurchase program will have a dilutive effect on our existing stockholders.

• The amount of distributions we may make is uncertain. We have paid and may continue to pay distributions from sources other than our cash flow from operations. Distributions paid from sources other than our cash flow from operations represent a return of capital. We have not established a limit on the amount of proceeds from our public offering that we may use to fund distributions. This could result in fewer funds available for investments and your overall return may be reduced.

• The offering price of our shares was not established based upon appraisals of assets we own or may own; therefore, the offering price may not accurately reflect the value of our assets when you invest.

• We will depend upon our advisor to conduct our operations. Adverse changes in the financial health of our advisor could cause our operations to suffer.

• All of our executive officers and some of our directors are also officers, managers, directors and/or holders of a controlling interest in our advisor, the dealer manager and other sponsor-affiliated entities. They will face conflicts of interest, including conflicts created by compensation arrangements, time constraints and competition for investments.

• We pay substantial fees to our advisor and its affiliates, including the dealer manager. These fees were not negotiated at arm’s length and may be higher than fees payable to unaffiliated third parties.

• We may be obligated to pay our advisor a subordinated distribution upon termination or non-renewal of the advisory agreement, with or without cause, which may be substantial and therefore may discourage us from terminating the advisor.

• The success of our public offering depends on the ability of the dealer manager to successfully market our offering. If we raise substantially less than the maximum offering amount, we may not be able to invest in a diverse portfolio of assets and the value of your investment may vary more widely with the performance of specific assets.

• We may incur debt exceeding 75% of the aggregate cost of our assets. High debt levels increase the risk of your investment. Loans we obtain may be collateralized by some or all of our investments, which will put those investments at risk of forfeiture if we are unable to pay our debts. Principal and interest payments on these loans reduce the amount of money that would otherwise be available for other purposes.

• Failure to qualify as a REIT would adversely affect our operations and our ability to make distributions to our stockholders because we would be subject to U.S. federal income tax and applicable state and local income taxes at regular corporate rates and would be unable to deduct distributions made to our stockholders.

Dear Potential Investor:

Thank you for reviewing Steadfast Apartment REIT III. I hope you’ll consider joining us by investing in today’s growing movement toward apartment living in the United States.

THE RIGHT SECTOR

Apartment communities are a critical component of the housing market in America today. In the pages that follow, we outline the compelling demographic forces that propel our belief that many Americans will continue to choose apartments as their homes—from young Millennials just getting started, to our nation’s aging Baby Boomers who are retiring.

THE RIGHT STRATEGY

These demographic forces support our investment strategy, in which we plan to acquire established midtier apartment properties and senior living facilities in high-demand neighborhoods, and then make capital improvements selectively, where we feel the extra investment can produce greater value.

Owning shares in Steadfast Apartment REIT III may be a passive investment for our shareholders, but it is certainly not a passive investment for those of us who manage and sponsor it at Steadfast Companies.

We are a true real estate operating company, and the performance of this company will be based on the results of our strategic location selection, underwriting acumen, operational enhancements and capital improvements.

We believe that your Steadfast Apartment REIT III investment is as much an investment in the real estate portfolio we are building as it is an investment in our ability to create value.

THE RIGHT SPONSOR

Over the years, Steadfast Companies has grown to become a diverse, multifaceted real estate investment management company with a team of 2,100 dedicated professionals. We bring our collective experience, wisdom and track records to bear on behalf of our investors, partners and residents.

As an investor in Steadfast Apartment REIT III, you can feel confident that you are doing business with an established sponsor company that has long been committed to performance, quality and integrity.

THE RIGHT FIT

We believe the Steadfast Apartment REIT III opportunity is structured in a way that supports the goals of many investors. We seek to provide regular cash distributions with potential for long-term growth in the value of your investment, while also providing capital preservation and a hedge against inflation. Following your evaluation of our offering, we hope you find that it’s the right fit for your investment needs.

Sincerely,

Rodney F. EmeryRodney F. Emery, President & Chief Executive Officer,Steadfast Companies & Steadfast Apartment REIT I I I

2

Apartments are already an important part of the real estate market, and we believe they are likely to experience positive gains over the coming years.

COMMANDING PART OF U.S. ECONOMYApartments contribute $1.3 trillion annually to our national economy,¹ and are second only to retail in market capitalization and industrial in square footage.²

HIGH OCCUPANCY LEVELSDue to the strong, consistent demandfor apartments, occupancy for thepast 20 years has averaged 94%.³

SOLID RENTAL REVENUEApartments have had annual rentalgains 17 of the past 20 years.³

HEDGE AGAINST INFLATIONIn recent decades, only apartments have enjoyed rental growth that has beat inflation across the major commercial real estate sectors.⁴ This is largely due to short lease durations—allowing apartment owners to adjust rents more than once per year, and providing considerable responsiveness to changes in both demand and expenses.* This sensitivity can result in near-term declines in rental growth; however, apartments’ short-term leases ultimately allow for more rapid recoveries, while long-term leases can result in “locking in” lower rental rates negotiated during temporary economic downturns.

Apartment sector offers chance to capitalize on strength.

**

*

2% 4%

APARTMENTS

ANNUALRETURN

STANDARD DEVIATION**6% 8% 10% 12% 14%

6%

7%

8%

9%

10%

11%

HISTORICAL PERFORMANCE OFVARIOUS PROPERTY TYPES (1978 -2016)4

COMMUNITY RETAIL

REGIONAL MALLS

WAREHOUSE

R&D/FLEX OFFICE

CBD OFFICE

SUBURBAN OFFICE

BEST

RISK

ADJUSTE

D RET

URN

WORST RISK

ADJUSTED RETURN

1 National Multi Housing Council and National Apartment Association, Apartments Contribute $1.3 Trillion to the Economy, May 2017

2 UrbanLand, Journal of Real Estate Portfolio Management3 Axiometrics, U.S. Census Bureau4 Joseph L. Pagliari Jr., Some Thoughts on Greatest Hits (and Misses)!, October 6, 2016. Based on historical transactional data provided by the National Council of Real Estate Investment Fiduciaries

BEST RISK-ADJUSTED RETURNSApartments have historically had the best risk-adjusted returns in real estate.4 Standard deviation is a statistical measurement of the deviation of a set of numbers from their average. For investments, standard deviation is considered to measure how returns vary over time (or deviate) from the average return and, hence, measures the volatility of investment returns. To the extent that volatility is a proxy for investment risk, standard deviation can be used as an objective measurement of risk. Of course, the prior volatility of an investment or class of investments is no guarantee of future volatility.

THERIGHTS E CTOR

3

300,000NEW APARTMENTS

NEEDED ANNUALLY1

650,000 UNIT DEFICIT

AFTER 7 YEARS OFLACKLUSTER COMPLETIONS6

New apartment supply is not keeping up with demand, and supply of midtier apartments

has actually decreased since 2002.5

Increasing demand for apartments surpasses supply.

5 Wall Street Journal, Rents Rise Faster for Midtier Apartments than Luxury Ones, August 16, 20156 U.S. Census Bureau 7 Urban Institute, We are Not Prepared for the Growth in Rental Demand, June 24, 2015

“Demand for rental housing over the next 15 years will dramatically increase—and we as a nation are not prepared.”7

FACTORS LEADING TO CONTINUEDDEMAND/ SUPPLY IMBALANCE

RE

DU

CE

DS

UP

PLY

• Significant post- recession construction decline• Multi-year development timeframe for new projects• New supply focused on luxury product in select U.S. markets • Rising construction costs too high to build middle-income housing

• Growing U.S. population • Fundamental human need for shelter• Paradigm shift in ownership preferences• Tightened lending standards• Rising interest rate impact on mortgage cost

INC

RE

AS

ING

DE

MA

ND

4

THERIGHTS E CTOR

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America is on pace to reach 40 percent rentership.8

Renting has increased among all age groups, household types and income groups, and we expect up to 7 million new rental households by 2020.9

Specifically, two groups—the two largest generations in U.S. history—are changing how America lives: maturing Millennials and retiring Baby Boomers.

MILLENNIALSRather than aspiring to early homeownership, young people born between 1981 and 1992 associate owning homes with expense, immobility and foreclosure. They want the freedom to frequently change jobs, careers and residences.

Higher-income college graduates are expected to rent longer than in the past, due in part to ever increasing student loan debt that is expected to impact their housing choices for decades to come.10

AxiometricsNational Multi Housing Council and National Apartment Association, The Trillion Dollar Apartment Industry, February 2013 National Housing Conference, Housing’s Lost Decade: Where We Go from Here, January 201 3 CNN Money, Is Student Loan Debt Hurting the Housing Recovery?, September 2014

Individuals under the age of 35 have the highest propensity to rent and by 2019 Millennials will hit an all-time high of 75 million.8

75MILLION

201 9

20-34 YEAR-OLDPOPULATION8

20 14

57MILLION

America has become a GenerationALL renting society.

$250PER MONTH IN

STUDENT LOANS11

6M I L L I O N

AMERICANS PAY

20-34 YEAR-OLDPOPULATION

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

8.0%

9.0%

10.0%

11.0%

12.0%

37%

38%

39%

40%

41%

42%

43%

44%

45%

46%

47%

48%

49%

50%

2003

2004

2005

2006

2007

2008

2009

2010

20

11

2012

2013

20

14

2015

2016

F

2017

F

2018

F

2019

F

2020

F

2021

F

U.S. MILLENNIALS HOMEOWNERSHIP RATE AND COLLEGE DEBT

Homeownership Rate (Age Group 25-34 Years Old) % Share of College Debt to All HH Debt

Sources: Axiometrics Inc. [April 2017], Census, Federal Reserve Bank of NY [2003-2016]

8

9

10

11

5

THERIGHTS E CTOR

THERIGHTS E CTOR

THERIGHTS E CTOR

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BABY BOOMERSMany seniors are transitioning from owning to renting because of age, reduced income, health, divorce, widowhood, a desire to simplify, or after becoming “empty nesters.” As a result, demand for senior housing is expected to increase by 20,000 units per year for the next 25 years.12

What Does GenerationALL

Mean?GenerationALL is our term to highlight the broadening demographic spectrum of young Millennials through aging Baby Boomers that are increasingly choosing to rent.

Steadfast Apartment REIT III will focus primarily on meeting the growing needs of these Americans that are seeking quality midtier apartments and senior living facilities.

12 Wells Fargo, Wells Fargo Expands Senior Housing Focus to Address Growing Demand, April 21, 201513 National Multifamily Housing Council, 2015 NMHC Research Forum, April 2015

52% of seniors between the ages of 65-80 that recently moved became renters.9

57%INCREASE

IN DEMANDFOR SENIOR

RENTALHOUSING

BETWEEN 2015-202513

YOUNGPROFESSIONALS

FAMILIESWITH

CHILDREN

RETIREES

THERIGHTSTRATEGY

THERIGHTS E CTOR

6

A compellingstrategy. Steadfast Apartment REIT III intends to acquire a strategic portfolio of quality, midtier rental housing that appeals to multi-generational groups as they age through their housing needs. We will utilize a comprehensive four-part strategy as we build and operate our portfolio.

1. Target the right markets.

When determining what markets to target for investment, we will look at a number of factors that we believe have the greatest potential to impact apartment growth, and will focus on markets that rank highly in key areas:

• ROBUST POPULATION GROWTH

• DECLINING VACANCY RATES

• HEALTHY MIDDLE-CLASS INCOMES

• ABOVE-AVERAGE JOB GROWTH

• INCREASING HOUSEHOLD FORMATION AMONG POTENTIAL RENTERS

• REASONABLE NEW SUPPLY RELATIVE TO DEMAND

TARGETED INVESTMENT MARKETS

THERIGHTSTRATEGY

7

U.S. RENTER HOUSEHOLDS BY AGE (IN ’000)25-34 YEARS OLDS 35-44 YEARS OLDS 45-54 YEARS OLDS 55-64 YEARS OLDS

Sources Axiometrics Inc. [April 2017], Census [2000-2016]

20

00

20

01

20

02

20

03

20

04

20

05

20

06

20

07

20

08

20

09

20

10

20

11

20

12

20

13

20

14

20

15

20

16

20

17F

20

18F

20

19F

20

20

F

20

21F

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

11,000

12,000

13,000

14,000

9,993 9,81010,580

12,19312,556

2,6783,488

5,171

6,2945,935

2. Acquire properties that appeal to GenerationALL renters.

We are focused on the specific groups of Americans with the highest propensity to rent, and we seek to acquire property types that appeal to their lifestyles.*

MILLENNIALSWe believe that individuals under 35 often seek downtown loft conversions and residential-tower settings that provide them with the ability to drive, walk, bike or take public transit to their job, dining or entertainment options.

FAMILIES WITH CHILDRENWe believe this group of renters may prefer to own a home, but they have been priced out of the market. They are attracted to high amenity suburban areas with townhome-style layouts, garages and gated entries. BABY BOOMERSWe believe seniors today are looking for age-restricted communities and senior housing facilities that provide “age-in-place” rental living, and offer on-site maintenance, organized activities, easy access to healthcare and, as necessary, assistance with meals, mobility and daily living activities.

We may invest in select senior living communities that provide amenities for

residents 55 years of age or older. We will not invest in communities that

provide healthcare services.

* We intend to comply with all provisions of the Fair Housing Act and the Housing for Older Persons Act

TARGETEDSENIOR LIVINGINVESTMENTS

AgeRestrictedHousing

IndependentLiving

MemoryCare

AssistedLiving

SkilledNursing

RehabFacilities

Hospitals

LOW-ACUITY

MID-ACUITY

• Choice Driven• Low Regulation• Private Pay

HIGH -ACUITY• Need Driven• High Regulation• Government Pay

8

THERIGHTSTRATEGY

THERIGHTSTRATEGY

3. Cater to renters’ preferences.

As Americans increasingly realize they can call a place “home” without actually owning it, we believe we can provide a competitive edge by offering rental options that respond to the preferences of today’s renters and creates an environment where residents are likely to rent longer.

AFFORDABILITY With more than one in four renters now spending over half their family income to pay for housing and utilities, the share of cost-burdened individuals now includes those whose incomes reach $75,000—underscoring a growing concern that America’s housing is increasingly becoming a larger percentage of people’s paychecks.14 We will seek to acquire properties that provide moderate income housing affordable to the average American.

MODERN AMENITIESMany renters are seeking outdoor dining areas, on-site gyms, swimming pools, libraries, even theater screening rooms and community gardens—all of which foster a sense of community and friendship among residents.

Additionally, amenities like garages, washers and dryers, soaking tubs and walk-in closets reflect the preference of today’s renters.

PET FRIENDLINESSPet ownership in the United States has been rising steadily for decades, and pet ownership among renters surged by 46 percent from 2006 to 201 1.15 We believe that offering amenities like dog parks, grooming stations, dog-walking services and even day-boarding service broadens appeal and encourages people to rent longer.

We will seek apartment

communities that serve

middle-class Americans —

the largest population group,

with 52%* of households

falling in this category.

Class C & Subsidized Housing Tenants

Typical Middle Market Renters

High-End Apartment/Single-Family Residence Renters and Homeowners

* U.S. Census Bureau, Current Population Survey, 2015 Annual Social & Economic

Supplement

TARGET RENT RANGE:$625 - $1,50020%

UNDER$15K

$35K-$49,999

$15K-$24,999

$25K-$34,999

$100K-$149,999

$150K-& OVER

$50K-$74,999

$75K-$99,999

18%

16%

14%

12%

10%

8%

HOUSEHOLD INCOME

U.S

. P

ER

CE

NT

AG

E O

F H

OU

SE

HO

LD

S*

14 Axiometrics15 UrbanLand, Going to the Dogs: Profitable Pet-Friendly Amenities, August 2014

9

THERIGHTSTRATEGY

4. Enhance value wisely.

At Steadfast, we seek opportunities to convert good properties into better ones by introducing our extensive institutional resources to under-managed real estate.

At these properties, we have found that making comparatively minor aesthetic improvements can have a significant and disproportionate impact on the property’s revenue and resale value.*

BEFORE AFTER

STEADFAST’S VALUEENHANCEMENT STRATEGY*

Paint & wall coverings

New appliances & countertops

Lighting & fixtures

Upgradedflooring

STEADFAST’S VALUEENHANCEMENT STRATEGY*

Paint & wall coverings

New appliances & countertops

Lighting & fixtures

Upgradedflooring

Beyond our universal practice of pursuing operational excellence, we expect that 50% - 70% of our properties will undergo strategic property-level enhancements.

We intend to implement the majority of interior improvements while units are vacant to limit the disruption to residents and the impact on the property’s revenue.

These opportunities will vary in degree, but generally will deploy the following methodology:

1. Purchase valuable—but somewhat under-managed– communities from sellers who were not realizing the potential of these properties

2. Revitalize communities with aesthetic improvements and strategic upgrades

3. Reposition assets in their markets to attract higher- paying residents

4. Sell assets at a premium due to increased yield and property quality

*There is no guarantee that we will realize growth in the value of our value enhancement properties.

SMALLCHANGES

BIGIMPACT

THERIGHTSPONSOR

THERIGHTSPONSOR

10

Unlike many financial services companies that offer real estate investment programs, Steadfast Companies is a real estate company first and foremost.

We continuously position ourselves to capitalize on changing environments and embrace opportunities in real estate investing for the benefit of investors, partners, residents, tenants and the community.

C O R E VA LU E S

• 23-YEAR HISTORY

• OVER $6.6 BILLION ACQUIRED, DEVELOPED OR REDEVELOPED

• STRONG INSTITUTIONAL RELATIONSHIPS

• 2,100 TALENTED PROFESSIONALS

• NEARLY $1.9 BILLION IN NON-TRADED REIT CAPITAL RAISED

• SPONSORED 50 PRIVATE AND PUBLIC INVESTMENT PROGRAMS

• INVESTMENT MANAGEMENT FOR 150+ RETAIL, APARTMENT, OFFICE AND HOTEL PROPERTIES

• EXTENSIVE EXPERIENCE IN ACQUISITION, CONSTRUCTION MANAGEMENT, PROPERTY MANAGEMENT AND DISPOSITION

Steadfast is tested and proven.

PROCEEDWITH

INTEGRITY

EMBRACEOPPORTUNITY

PURSUEEXCELLENCE

DO GOODAS WE DO

WELL

VALUEPEOPLE

Steadfast owns, operates and/or manages

$4.6 billion of real estate,

including more than 38,000 apartment

homes across 22 states.

The information above is specific to Steadfast Companies, the sponsor of Steadfast Apartment REIT III, and reflects properties owned and/or managed. Investors are not making an investment in Steadfast Companies. Past performance is no guarantee of future results.

THERIGHTSPONSOR

THERIGHTSPONSOR

11

We believe we can drive value in our portfolio by:

• Selectively investing in markets that are often overlooked by other real estate firms

• Actively managing each property to achieve operational efficiencies and higher occupancies

• Consistently maximizing our institutional experience and resources to optimize asset appreciation and maximize our profit potential

STEADFAST’S INTEGRATED ASSET STRATEGYSteadfast Companies’ signature Integrated Asset Strategy capitalizes on real estate experience and sound investment planning to actively manage each acquisition from site selection through disposition.

Steadfast is a real estate company focused on value creation.

132-POINT CHECKLIST

REGIONAL MANAGEMENT

TOTAL PERFORMANCE-BASEDBONUS STRUCTURE

CONTINUOUS ANALYSIS

ACQUISITION

ASSETMANAGEMENT

REDEVELOPMENT

ACCOUNTING

MARKETING& LEASING

PROPERTY MANAGEMENT

STEADFAST’S INTEGRATED ASSET STRATEGY

THERIGHTFIT

THERIGHTFIT

THERIGHTFIT

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12

INVESTOR SUITABILITY** Our shares of common stock are suitable only as a long-term investment for people of adequate financial means. Thus, we have established suitability standards for initial stockholders and subsequent transferee's:

• a net worth (excluding the value of an investor’s home, furnishings and automobiles) of at least $250,000; or

• a gross annual income of at least $70,000 and a net worth (excluding the value of an investor’s home, furnishings and automobiles) of at least $70,000.

OFFERING SIZE/MINIMUM INVESTMENTWe are offering up to $1.3 billion in shares of our common stock. You must initially invest at least $5,000 in our shares; however, for qualified accounts the minimum investment is $2,500 with additional investments in $100 increments.

LEARN MORE ABOUT STEADFAST APARTMENT REIT III. Consult with your financial advisor today to determine how Steadfast Apartment REIT III can fit with and benefit your investment portfolio.

Is Steadfast Apartment REIT III the right fit for your portfolio?

IT’S TIMETO MAKE

SURE YOUR INVESTMENTSWORK HARD

FOR YOU.

FOR INVESTORS SEEKING*...

WHY FOCUS ON “GenerationALL”

STABLE CASH FLOWS*

CAPITAL APPRECIATION

DIVERSIFICATION*

INFLATION PROTECTION*

ATTRACTIVE RISK-ADJUSTED RETURNS

*There is no guarantee the Company will meet its objectives. Distributions are not guaranteed and may be paid from sources other than operating activities, including borrowings and o�ering proceeds. Diversification does not ensure a profit or guarantee against a loss. Our operating results will be a�ected by economic and regulatory changes that impact the real estate market in general.

** Certain states have different/additional suitability standards; see the prospectus for more information.

THERIGHTFIT

THERIGHTFIT

THERIGHTFIT

THERIGHTFIT

13

Steadfast Apartment REIT III offers an opportunity to invest in the RIGHT sector of real estate, governed by the RIGHT investment strategy that focuses on high-demand markets, led by the RIGHT sponsor and its experienced management team. Please discuss with your financial advisor to determine if we’re the RIGHT fit for you.

14

18100 Von Karman Avenue, Suite 500Irvine, CA 92612

(877) 525-7264 • SteadfastREITS.com

Steadfast Apartment REIT III is sponsored by Steadfast REIT Investments, LLC, an affiliate of Steadfast Companies. Stira Capital Markets Group, LLC, Member FINRA & SIPC, is the dealer

manager for the Steadfast Apartment REIT III, Inc. offering.

STAR3-BR05-1117

Not a Deposit Not FDIC Insured Not Guaranteed by the Bank

May Lose Value Not insured by any Federal Government Agency