In the event the suspected father or mother is unavailable for a paternity or maternity test, a sibling DNA test is the only realistic way to determine whether 2 people are siblings.
The Best Sibling DNA Test Kits Reviewed
Over 26 million people have taken at-home DNA tests, for reasons ranging from curiosity about their family history and genealogy to legal concerns such as having to prove their paternity in court cases.
In some cases, siblings have had to prove their paternity to receive survivor benefits from a deceased father or to prove their relationship in immigration hearings. In other situations, siblings whose parents’ marriage ended in divorce might wonder if they have half-brothers or half-sisters that they don’t know about.
No siblings share 100% of their DNA, not even identical twins. Fortunately, though, you can find out how closely you and your sibling are related using one of the sibling DNA test kits reviewed in this article.
Our Top 10 Best Sibling DNA Test Kit in 2023:
- MyHeritage - Best sibling DNA test overall
- AncestryDNA - Best for large database of people available
- LivingDNA - Best value for basic package
- 23andMe - Best for genetics and deeper ancestry information
- Vitagene - Best for high accuracy
- EasyDNA - Best for quick results
- Family Tree DNA - Best paternal line tests
- Legacy Tree Genealogists - Best for genealogy research
- International Biosciences - Best for scientific reliability
- HomeDNA Direct - Best for at-home sampling kit
Our Picks for the Top 10 Best Sibling DNA Test Kits - Quick Reviews
Not sure which sibling DNA kit to go with? Here is our round-up of the top 10 DNA test kits - for twins and siblings - worth checking out.
- Price: $69
- Test type: Cheek swab
- Results: 4 weeks
Everyone who takes a MyHeritage DNA test or uploads their DNA data to MyHeritage receives a list of DNA matches from MyHeritage’s database of more than 1 million people. If 2 people wish to prove they are siblings, all they need to do is use MyHeritage’s DNA service to see if they’re a match. MyHeritage can deliver close to 100% accuracy for a sibling relationship and around 93% accuracy for distant relatives like fourth cousins.
- Huge database of users
- Website provides free basic family tree and photo features
- Access to vast record library
- Health risk report requires paid upgrade
- Full-featured family tree services are expensive
- Price: $99
- Test type: Saliva
- Results: 6-8 weeks
Everyone who takes an Ancestry DNA test or uploads their DNA data to the Ancestry system can see a list of DNA matches from Ancestry’s database, which is the world’s largest with more than 5 million people. Sibling relationships can be proved at close to 100% accuracy, or beyond reasonable doubt.
- Huge database of over 15 million people
- Adds family tree connections based on DNA
- Vast research library of billions of records
- More expensive than other tests
- Saliva sample is less convenient
- Price: $89
- Test type: Cheek swab
- Results: 4-6 weeks
Anyone can take a LivingDNA test or upload data from other tests to see who they match with in the LivingDNA database. This is the only DNA kit that has a basic package with motherline, fatherline, and distant relatives included.
- Advanced details for Africa, Europe, and British Isles
- Haplogroup reports give ancient ancestry
- Portal is easy to navigate
- Relative newcomer to DNA testing market
- Smaller user database than market leaders
- Price: $99
- Test type: Saliva
- Results: 6-8 weeks
23andMe doesn’t offer specific sibling tests, though its comprehensive DNA packages will give you all the tools to find out if you’re a match. One of the leaders in the DNA industry, it offers an accurate, in-depth look at ancestry composition and detail as well as maternal and paternal haplogroups. You can see an anonymous list of DNA family around the globe, and opt in to connect with them.
- Excellent genetic health information
- Haplogroup reports show ancient roots
- Gives estimate of Neanderthal heritage
- No genealogy research available
- Health test requires upgrade
- Price: $89
- Test type: Saliva
- Results: 4-6 weeks
Though Vitagene only offers individual tests, potential siblings can compare results gleaned from its cutting edge lab. Backed by researchers and professors from Stanford University and Berkeley, Vitagene provides a detailed look at each person’s genetic makeup through genotype testing. What distinguishes this company is it’s tandem mission of wellness; it offers health reports that can help you and your relatives trace potential health factors and take preventative measures specific to your report.
- Useful wellness tips
- Supplement advice based on DNA
- Offers health add-on if you already have DNA data
- Low level of detail for ancestry report
- Website FAQs are limited
Test Type: cheek swab
Results: 3-5 working days
EasyDNA provides a wide range of relationship test kits. Its Sibling DNA Test can help you determine whether you and your brother or sister share one biological parent, both biological parents, or none. It provides both peace of mind tests and legal tests, and the turnaround time of three to five days makes it an excellent choice for legal tests.
A handy chat feature on the website makes it easy to connect with EasyDNA’s experts to determine which of your family members are available for testing and which kit you need. Collection kits for the sample DNA are then sent to you as soon as your order is confirmed. The kits contain swabs for the number of people you have specified to be tested.
Fast three- to five-day turnaround time
Testing for a high number of genetic markers increases accuracy
Offers both peace of mind and legal sibling DNA tests
More expensive than competitors
The number of possible test options can be overwhelming
7. Family Tree DNA
Test Type: cheek swab
Results: 2-4 weeks
If your interest in sibling DNA testing is for genealogical reasons or peace of mind, Family Tree DNA may suit your needs. You can use its Family Finder test to identify your sibling relationships, but you can also discover fascinating information about your ethnicity and your ancestors. Note, however, that Family Tree DNA does not offer legal sibling DNA tests. But if you are more interested in exploring your genetic ancestry with your sibling and interacting with a database of living relatives who have also used this service, this kit is an excellent choice.
Discover new relatives and their geographic background
Contact unknown relatives in the database who are a DNA match
Can upload your DNA data from other sites
Need to purchase two kits, one for each person
Not ideal for those testing for legal reasons
8. Legacy Tree Genealogists
- Price per kit: N/A
- Result in: 4-6 months
- Best for: Relying on professional genealogists for research
Legacy Tree Genealogists can analyze other companies' results (like AncestryDNA, MyHeritage, 23andMe, and Family Tree DNA), helping you make sense of data for sibling DNA matching. Their services are on the extensive side, as Legacy Tree is a professional ancestry research service that puts professional genealogists in charge of researching your family history. Complete family tree research projects take 4-6 months to complete. At the end of the process, you receive a detailed report explaining what the Legacy Tree research team discovered. You can contact Legacy Tree Genealogists and they will help customize your project according to your needs.
Access to professional genealogy researchers
Choose your own research goal
Shareable, easy to read report
Costly research packages
No DIY tree-building tools
9. International Biosciences
- Price per kit: From $119
- Result in: 5-7 days
- Best for: Reliable DNA tests that are checked twice
International Biosciences offers a broad range of DNA testing and paternity testing services, based in the UK with an international network of offices. It works with accredited labs around the world to provide you with the best service, and though its tests are not the cheapest on the marketing, they’re high quality and very accurate. The company even has a quality assurance program in place in order to provide you with the most accurate results.
- Quick and painless testing
- Data analyzed by accredited labs
- High-level customer service
- Not the cheapest on the market
- NY residents can only use some tests for legal purposes
10. HomeDNA Direct
- Price per kit: $299
- Result in: 5-7 days
- Best for: DNA test-taking enthusiasts of all kinds
HomeDNA Direct is an at-home DNA test kit provider that offers a large variety of test kit products. Beyond their wide range of test kits, like paternity or ancestry tests, they also offer relationship tests. These can help you to determine your degree of biological relationship with siblings.
Regardless of the DNA test kit you use, HomeDNA allows you to download your raw data free of charge. You will receive your results after 6 weeks, and all your data will be permanently stored online in a secure fashion. With affordable pricing, a thorough FAQ, and multiple support channels, HomeDNA’s tests are easy to purchase, use, and interpret.
- Large selection of test kits
- Provides access to raw data
- Detailed, very specific results
- No family tree services
- Cannot expedite results for most tests
What Is a Sibling DNA Test?
A DNA sibling test takes one person’s DNA profile and compares it to the DNA profile of another person. The aim of the test is to determine the likelihood that the two individuals have a biological relationship as siblings. Sibling DNA tests are often used to determine whether two people have the same father.
But they can also be used to provide proof of biological relationships for immigration purposes, to discover whether a child given up for adoption might be your brother or sister, or to learn more about your family.
How Does a Sibling DNA Test Work?
The test uses submitted saliva or cheek swab samples to establish a DNA profile for each person and to determine how closely they are related. If you are seeking a relationship report for one or more of your siblings, each of them must submit a sample or already be present in the company’s DNA database if they’ve previously been tested. The company then compares the two DNA profiles to determine a probability percentage that shows how likely it is that these individuals are your full or half-siblings.
These tests are effective because you and your siblings inherit half of your DNA from each of your parents. The DNA of full and half-siblings has more genetic material in common than would be found with a non-relative.
Different Types of Sibling DNA Tests
Full siblings are brothers or sisters who share both parents. For this reason, a full DNA siblings test is the most extensive type of sibling test. Rather than testing to see whether they are siblings or unrelated, full sibling tests compare genetic markers between two people to determine whether they have both parents in common. These tests analyze how much genetic material they share because full siblings typically share about 50% of their DNA.
You may be wondering, can a DNA test prove half-siblings? A half-siblings DNA test works under the same principles, but the test is meant to identify only a single shared parent. The measure of confirmation is 25% shared DNA.
Sibling DNA tests also differ in how they are to be used. Many people seek such tests out of curiosity or to learn more about their family history. These tests are referred to as peace of mind tests. Sometimes the tests are intended to be used as evidence in court proceedings, which requires a legal sibling test. Both types of tests are accurate, but the sample collection procedures for legal sibling tests are more stringent.
Choosing the Right Sibling DNA Test Kit
The following are some suggestions for how to select the sibling DNA test kit that is right for you.
Ask yourself, “Why do I need this sibling DNA test?”
Are you looking for sibling DNA test results to learn more about your family, or do you need legal sibling DNA test results that could be used in a court of law? Not all companies can provide legal sibling DNA reports.
Those that do usually charge extra for them because the legal tests require that the saliva samples be taken by a doctor or nurse and that proper chain of custody procedures are followed when submitting them.
Ensuring Privacy of Your DNA Data
If privacy is a concern for you, make sure that your DNA data or family tree information is not shared with outside agencies such as law enforcement.
Availability of DNA Data Export
One factor that many people don't consider when choosing a DNA test provider is whether the company can re-use the data on other ancestry and DNA testing sites.
If your test results leave you curious and wanting to know more about your ancestors and where they came from, can you upload your data to a service that provides that information and save yourself the trouble of submitting new samples?
Searching for Potential Long-Lost Siblings
Most purchasers of a home DNA test for siblings submit saliva samples for the siblings they know about. But some are trying to locate a brother or sister they have lost contact with or discover whether they have a sibling they didn’t know about.
If this is your goal, you should choose a DNA test provider with a large DNA database. The larger the database, the greater the chances that the company can find a match.
Do Siblings Share the Same DNA?
The short answer is no. Two closely related individuals, such as a brother and sister, can have similar DNA, but the odds of having the same DNA as someone other than an identical twin are roughly 1 in 70 trillion. According to recent studies, even identical twins share very similar, but not identical, genes.
Why Siblings Can Get Different Results from DNA Ancestry Tests
Every child inherits half of their DNA from their mother, through the egg, and half of their DNA from their father, through the sperm. But when sperm or eggs are created, the cells undergo a process called genetic recombination which sees the number of chromosomes halve from 46 to 23. When an egg is fertilized by a sperm, they combine to form a new package of 46 chromosomes.
As a result, the DNA one child inherits from their mother and father differs from the DNA their sibling inherits from their mother and father. On average, a pair of siblings share about 50 percent of the same DNA.
How Much DNA do Siblings Share?
On average, siblings share around half the same DNA, but the real figure is different for every sibling pairing. The more diverse their recent ancestors, the less DNA 2 siblings are likely to share. For example, 2 siblings with grandparents who were biracial or who came from different parts of the world would have a greater variety of potential genetic combinations.
As a result, it is likely they would share a smaller percentage of their DNA. Two siblings whose grandparents all had the same ethnicity or who all came from the same part of the globe would be likely to share a relatively high proportion of DNA.
Can Sibling Relationships be Proven through DNA Testing?
No DNA test can prove with 100% certainty that 2 people are siblings or otherwise related, but what they can determine is the likelihood.
Good sibling DNA tests compare 2 people based on at least 700,000 markers and are able to prove more than a 99% likelihood of the 2 being siblings, putting the matter beyond reasonable doubt.
How Accurate Are Sibling DNA Tests?
Without getting into too much detail, a person has a 50% chance of getting the same gene locus from each parent, so you and your sibling have a 25% chance of getting the same matching locus combination from your parents.
Thanks to improved testing methods that compare DNA between 2 individuals by more than 700,000 markers, sibling relationship can be proved with up to around 99.9% certainty.
How Can I Find Lost Siblings with the Test?
If you’ve made contact with a potential sibling, then all that needs to be done to prove the sibling relationship is for both of you to take a DNA test. If you’re hoping to find a long-lost sibling but haven’t found them, then taking a DNA test is a long shot—and success may depend on whether that sibling’s DNA data sits in the same database.
AncestryDNA has the world’s largest DNA database, with more than 5 million people. Therefore, the chances of finding a sibling in Ancestry’s database depend on whether or not a long-lost sibling happens to be among those 5 million people. Fortunately, a DNA test isn’t the only way to discover a potential sibling.
AncestryDNA, MyHeritage and others offer family tree builders that can help you discover relatives the old-fashioned way—through discovering a common link in the family tree. There are many stories out there of reunited siblings, such as the one last year of 2 Norwegians who discovered they were half siblings thanks to MyHeritage’s smart match.
Sibling DNA Testing for Twins
Siblings tests for twins are exactly the same as sibling tests for full siblings who didn’t share time in the womb. While identical twins share almost all their DNA, other types of full siblings—including fraternal twins—share only 50% of DNA, on average, thanks to the phenomenon known as genetic recombination.
Twin DNA testing can be used to confirm if 2 people are identical (monozygotic) twins or non-identical (dizygotic) twins. In some cases, such as the Olsen twins, two twins can look almost alike without technically being identical.
Only a DNA test can confirm this. Such a test might be needed if one twin needs an organ or tissue transplant, because an identical twin would be the optimal donor
Discover and Connect with Your Family
Tremendous gains have been made in home DNA testing kits in recent years, bringing us to the point where 2 people can prove with almost complete certainty whether or not they are siblings.
Likewise, the availability of DNA testing has improved to the point where any 2 people can discover if they're related within a month or so, for less than $100, and all with a cheek swab or a bit of saliva.