Your pediatrician says the words "let's keep an eye on it." Six months pass. Nothing changes. Now you want an answer, and a search bar hands you fifteen phone numbers with no instruction on which one to call first.
Here is the plain-English version. Learning how to get an autism diagnosis comes down to one thing: a formal autism evaluation and diagnosis by a qualified clinician who measures your child's development against DSM-5-TR criteria and writes it up in a report. Every state runs the same four steps. Raise the concern, complete a screening, get referred, finish the evaluation. What changes between Georgia, Tennessee, Virginia, North Carolina, and Maryland is which door you knock on first, and how fast that door is legally required to open.
How to Get an Autism Diagnosis: The Four Steps Behind Every State's Process
Step 1: Say it out loud at a well-child visit. The American Academy of Pediatrics recommends autism-specific screening at the 18-month and 24-month visits, in addition to general developmental screening at 9, 18, and 30 months. Susan Hyman, MD, of the University of Rochester Medical Center led the AAP's clinical report on identifying and managing autism, and one of its clearest messages is that caregiver concern belongs in the record. Say the specific thing you have noticed. Not "he seems behind," but "he does not respond to his name and he has stopped waving."
Step 2: Understand what a screening is. A screening tool flags risk. It does not diagnose. A positive result means your child needs a full evaluation, not that your child is autistic. A negative result does not close the question either. If the signs you noticed are still there in three months, bring them back.
Step 3: Make two referrals on the same day. This is the step most families skip, and it is the one that separates a seven-month timeline from a two-year one. One referral goes to your state's early intervention program, which is free and moves on a legal deadline. The other goes to a diagnostic provider, which is slower and usually involves a waitlist. Parents who figure out how to get an autism diagnosis efficiently are almost always the ones running both tracks in parallel rather than in sequence.
Step 4: Complete the evaluation. A comprehensive autism evaluation pulls in developmental history, caregiver interviews, direct structured observation using tools like the ADOS-2, and often input from speech or occupational therapy. It ends with a written report. That report is the document everything else depends on.
Who Diagnoses Autism, and Who Cannot
Parents lose months to this distinction, so it is worth being blunt about it.
Clinicians who can issue a medical diagnosis typically include developmental-behavioral pediatricians, licensed clinical psychologists, child neurologists, child psychiatrists, and in some settings a pediatrician with autism diagnostic training. State licensure rules vary, and some insurers name specific credentials in their policy language.
Programs that cannot issue a medical diagnosis include your state's early intervention system and your local school district. Early intervention determines eligibility for services based on developmental delay. That is a different question from whether your child meets the diagnostic criteria for autism.
Public schools operate under IDEA Part B and can find a child eligible for special education under the educational category of autism. That is an educational determination. It opens the door to an IEP. It generally does not satisfy a health plan's requirement for ABA authorization. Families are often surprised by this after a full school evaluation, so ask the question early: does my insurer accept this report?
Those reports are still worth having. They document delay, establish a service history, and give the diagnosing clinician useful observational data. Collect them and hand them over.
Where to Start Your Child's Autism Evaluation in Five States
In all five states Blossom serves, the fastest opening move is the same. Call the state's early intervention program before you have a diagnosis, because eligibility does not require one. Here is who to call.
Georgia: Babies Can't Wait
Georgia's Part C program is Babies Can't Wait, administered by the Georgia Department of Public Health through 18 public health districts covering every county. It serves children from birth to the third birthday. Referrals can be made by phone, email, fax, letter, or in person, and parental consent is not required for a referral source to make one. Families in Atlanta, Savannah, Augusta, and rural districts alike route through their local Child Health office. Once a child turns three, the referral shifts to the local school system.
Tennessee: Tennessee's Early Intervention System
TEIS is administered by the Tennessee Department of Disability and Aging, with a single statewide referral line and an online referral form that routes to the district office serving your county. Eligibility runs through documented delay thresholds, a qualifying diagnosis list, or prematurity criteria. Tennessee also offers the TEIS Extended Option, which allows some eligible families to continue with TEIS services past the third birthday rather than transitioning straight to the school system. That flexibility is unusual and worth asking about directly.
Virginia: Infant & Toddler Connection of Virginia
Virginia runs its Part C system through the Department of Behavioral Health and Developmental Services, and every city and county has a designated central point of entry. State regulation requires primary referral sources to refer a potentially eligible child within seven days of identifying them. Referrals arrive by phone, fax, mail, email, web form, or in person, and the local system must accept one even when the referring source has not yet told the family. Your central point of entry is a searchable local listing, not a statewide queue.
North Carolina: NC Infant-Toddler Program
The North Carolina Early Intervention Section, part of NCDHHS, oversees the Infant-Toddler Program through 16 Children's Developmental Services Agencies. Each CDSA covers a defined cluster of counties, from the Blue Ridge to Cape Fear. Referrals go directly to your CDSA by phone, email, fax, letter, in person, or by submitting the NC ITP referral form. Evaluation and service coordination carry no cost to families, and other services follow a sliding scale. For children already past their third birthday, the referral goes to the local school district instead.
Maryland: Maryland Infants and Toddlers Program
MITP is led by the Maryland State Department of Education and delivered through local programs in all 23 counties plus Baltimore City, with a statewide online referral portal. Maryland stands out for its Extended IFSP Option, which lets families of eligible children stay on an Individualized Family Service Plan past the third birthday, through the start of the school year following the child's fourth birthday, instead of moving to an IEP. Families choose. That choice is worth understanding before the transition meeting, not during it.
How Long Does It Take to Get an Autism Diagnosis?
Knowing how to get an autism diagnosis and knowing how fast it will happen are two different questions. There are two clocks running here, and only one of them carries a legal deadline.
The early intervention clock is federal law. Under IDEA Part C, the screening, initial evaluation, initial assessments, and the first IFSP meeting must all be completed within 45 days of referral. Narrow exceptions exist for family unavailability, but the timeline is a compliance requirement that states report on annually.
The diagnostic clock has no such deadline. CDC's Autism and Developmental Disabilities Monitoring Network found a median age of 47 months at earliest known autism diagnosis among 8-year-olds surveilled in 2022, even though reliable diagnosis is possible by age two. Peer-reviewed claims analysis published in the Journal of Managed Care & Specialty Pharmacy describes an average gap of close to three years between a caregiver's first concern and an eventual diagnosis. Georgia, Tennessee, and Maryland are all ADDM surveillance sites, so those figures reflect the region directly.
Three moves compress that gap:
Get on more than one diagnostic waitlist at the same time. Nothing prevents it.
Ask every office about its cancellation list and confirm you can be reached same-day.
Start early intervention services while you wait. Delay is not a prerequisite for anything.
What Has to Be in Place Before ABA Can Begin
A diagnosis alone is not a green light. Four things generally need to line up before therapy hours start:
A written diagnostic report that names autism spectrum disorder, cites DSM-5-TR criteria, lists the assessment tools used, and carries the evaluating clinician's credentials and date.
A referral or prescription for ABA, which many health plans require even when the diagnosis is already documented.
Insurance verification and prior authorization. Coverage rules differ meaningfully across the five states, which is why the diagnosis pathway and the coverage pathway are worth reading side by side.
A behavior assessment by a BCBA, which produces the treatment plan and the recommended hours submitted to your plan.
Families sometimes assume ABA therapy services are locked behind the final report, then discover paperwork could have moved in parallel. The question of whether a diagnosis is required before ABA has more nuance than most families expect, and the answer often depends on the plan rather than the clinic.
Three Mistakes That Quietly Add Months
The mechanics of how to get an autism diagnosis are not complicated. The sequencing is where families lose time, usually in one of three places.
Treating "wait and see" as a binding instruction. A recheck in six months costs nothing if development is on track and costs a developmental window if it is not. Accept the recheck and make the referrals anyway. Early intervention does not require a physician's permission.
Waiting on the diagnosis before touching anything else. Insurance verification, provider conversations, and early intervention services can all move before the report lands.
Accepting the first appointment date as final. Most families never ask about cancellation lists. A brief, polite call every few weeks changes your position in ways the original booking never reflected.
What Running Both Tracks Actually Looks Like
Here is a composite scenario drawn from the pattern our intake team sees most often. Details are illustrative rather than a single family's record.
A mother in Chattanooga notices her 18-month-old has stopped waving and does not turn when called. The pediatrician screens him, notes some risk, and suggests a recheck in six months.
Two months later she stops waiting. She calls TEIS herself, which anyone can do, and asks her pediatrician for a diagnostic referral the same week. TEIS completes the evaluation and holds the IFSP meeting inside the federal 45-day window. Speech services start at 22 months, with no diagnosis on file and no cost to the family.
Meanwhile she sits on two diagnostic waitlists and calls both monthly. The second one rings on a Tuesday with an opening that Friday. Diagnosis at 27 months. Insurance authorization roughly six weeks later.
Total elapsed time from her first phone call: about seven months. Had she waited for the diagnosis before touching early intervention, her son would have started services nearly a year later. The tracks are independent. Run them that way.
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The families who get answers fastest rarely have the best pediatrician or the shortest waitlist. They are the ones who stopped treating how to get an autism diagnosis as a single line and started treating it as two lines running side by side.
You do not need the whole map to make the next call. You just need to know which number is yours.
Bring us the piece you are stuck on: which early intervention office covers your county, what your plan will want in the report, or what to do with the months in between. Drop our team a line and we will help you sort the order of operations before another season goes by.
Frequently Asked Questions
How do you get an autism diagnosis for a child?
The short version of how to get an autism diagnosis is this: raise the concern at a well-child visit, complete a screening, then get referred for a comprehensive evaluation with a psychologist, developmental pediatrician, neurologist, or child psychiatrist.
How long does it take to get an autism diagnosis?
Early intervention must complete its evaluation within 45 days of referral under federal law, but private diagnostic waitlists have no deadline and commonly run several months or longer.
Who can diagnose autism in children?
Developmental-behavioral pediatricians, licensed clinical psychologists, child neurologists, and child psychiatrists are the most common diagnosing clinicians, though specific credential requirements vary by state and by insurer.
Can you get ABA therapy without an autism diagnosis?
Most health plans require a documented autism diagnosis before authorizing ABA, though early intervention services are available without one while a diagnostic evaluation is still pending.
How much does an autism diagnosis cost?
Cost depends on the provider type, the assessment tools used, and your plan, and most private insurance and state Medicaid programs cover medically necessary evaluations. Ask for the billing codes before the appointment.
What age can a child be diagnosed with autism?
Screening is recommended at 18 and 24 months, and a diagnosis by an experienced clinician can be considered reliable by age two, though the national median remains close to four years old.
Sources:
https://www.tn.gov/disability-and-aging/disability-aging-programs/teis.html
https://marylandpublicschools.org/programs/pages/special-education/mitp/index.aspx
