What’s the Difference Between ASL and BSL?
BSL
American Sign Language (ASL) and British Sign Language (BSL) are distinct natural languages. They are not signed versions of spoken American or British English, and knowing one does not normally enable someone to understand the other.
The clearest visible difference is their manual alphabets: ASL fingerspelling is generally one-handed, while BSL uses a two-handed alphabet. However, the distinction goes much deeper. ASL and BSL have different histories, vocabularies and grammatical systems.
This guide is an educational comparison based on specialist and official sources. It does not replace teaching from a qualified Deaf sign-language teacher. Individual signs and language use can vary by region, community, generation and context, so learners should consult signed demonstrations rather than rely on written descriptions alone.
ASL vs BSL at a glance
| Feature | ASL | BSL |
|---|---|---|
| Full name | American Sign Language | British Sign Language |
| Main geographical use | Primarily the United States and parts of Canada, with users and influence elsewhere | Great Britain, with regional variation; BSL is also used elsewhere by some signers |
| Language relationship | Developed through contact involving early American signing communities and French Sign Language | Belongs to the BANZSL language family, alongside Auslan and New Zealand Sign Language |
| Manual alphabet | Predominantly one-handed | Two-handed |
| Grammar | Has its own grammatical system; sign order depends on the construction and context | Has its own grammatical system; sign order depends on the construction and context |
| Fingerspelling | Used for names, terms without an established sign, clarification and other discourse functions | Used for names, places, clarification, English-derived forms and other functions |
| Mutual intelligibility | ASL and BSL are not generally mutually intelligible, although an occasional sign may look similar | |
What is American Sign Language?
ASL is a visual language used primarily by many Deaf and hard-of-hearing people in the United States and parts of Canada. The US National Institute on Deafness and Other Communication Disorders explains that ASL is a complete natural language with grammatical properties expressed through hand movements alongside facial and bodily signals.
It is therefore inaccurate to describe ASL as English communicated through gestures. Its vocabulary and grammar are independent of English, even though contact between the languages occurs. Signers may also move between different forms of signing according to their audience and circumstances.
ASL has historical links to French Sign Language and to sign languages already used in the United States. It consequently does not descend from BSL simply because spoken English is widespread in both countries.
Like spoken languages, ASL has social and regional varieties. Black ASL is an important variety shaped partly by the history of segregated Deaf education in the United States. Gallaudet University’s Black ASL Project documents its history and linguistic features; it should not be reduced to a slang version of ASL.
What is British Sign Language?
BSL is a natural visual language used principally by Deaf people in Great Britain, as well as by relatives, interpreters, educators and other signers. Meaning is created through combinations of handshape, orientation, location, movement, facial expression, mouth patterns and body position. These elements are linguistic rather than decorative.
BSL belongs to the language family commonly called BANZSL, which also includes Australian Sign Language (Auslan) and New Zealand Sign Language (NZSL). Saying that BSL is a “dialect of BANZSL” reverses the relationship: BANZSL is a scholarly family label, not a parent language. The languages have historical relationships and similarities, but they should not be treated as identical in vocabulary, grammar or present-day use.
The UK Government recognised BSL as a language in March 2003. The British Sign Language Act 2022 subsequently gave BSL legal recognition in England, Wales and Scotland and established reporting duties for UK government departments.
The 2022 Act does not extend to Northern Ireland, but that does not mean BSL lacks legal recognition there. BSL and Irish Sign Language (ISL) are separately recognised in Northern Ireland under the Sign Language Act (Northern Ireland) 2026, which received Royal Assent on 9 July 2026. The Northern Ireland legislation also provides a framework for promoting the two languages and improving access to public services.
For a broader introduction, read our guide to British Sign Language for beginners.
The main differences between ASL and BSL
1. They come from different language histories
National spoken languages do not determine national sign languages. ASL’s development was strongly influenced by French Sign Language and existing American signing practices. BSL developed in Britain and is historically related to Auslan and NZSL.
This helps explain why ASL and BSL differ despite English being prominent in the United States and Britain. It also shows why sign-language relationships cannot be inferred by comparing the spoken languages used nearby.
2. Their vocabularies are different
ASL and BSL have different conventional signs for many everyday ideas. There is no dependable basis for claiming that they share a fixed percentage such as 30 per cent of their vocabulary. A reliable comparison would need to define which regional varieties, meanings and datasets were being measured.
Two signs can resemble each other because they depict a similar feature, arose through contact or happen to use comparable movements. Visual resemblance does not establish a particular level of vocabulary overlap. In practical terms, ASL and BSL users should not assume that they can hold a detailed conversation without prior exposure, interpretation or another agreed communication strategy.
3. Their manual alphabets use different systems
ASL typically uses one hand to fingerspell the Roman alphabet. BSL uses a two-handed alphabet, with the dominant hand generally moving against or interacting with the non-dominant hand. Left-handed signers may reverse the roles.
A manual alphabet represents letters; it is not the whole language. A lexical sign conveys a recognised word or concept directly, whereas fingerspelling represents a written word letter by letter. For example, showing the lexical sign for “cat” is not the same task as fingerspelling C-A-T. Comparing those two things would be misleading.
See our illustrated introduction to the British Sign Language alphabet. Because a static picture cannot reliably show movement, orientation or transitions, use it only as an introduction and confirm each form through Deaf-led instruction and signed video.
4. Each language has its own grammar
ASL and BSL do not share one “basic structure”, and neither can be reduced to a rigid English-style word-order formula. Sign order can change with the type of sentence, information structure, verb and context. Both languages can use topic-comment constructions, but that is one available construction rather than a universal rule.
Facial expression, head movement, eye gaze and body posture may perform grammatical work. For example, non-manual signals can help mark questions or show how information is organised. Translating an English sentence by rearranging its words—such as turning “The man is walking on the road” into a fixed three-word sequence—does not reliably produce grammatical BSL or ASL.
A useful learning mechanism is meaning first, construction second: decide what information you need to communicate, observe how fluent signers express that meaning in the relevant language, and practise the complete signed construction. Do not translate English one word at a time.
5. Fingerspelling has several functions
In both ASL and BSL, fingerspelling can identify personal names, place names and specialist terms. It can also introduce an unfamiliar word, disambiguate a sign, emphasise a written form or contribute to established vocabulary. Its frequency and function vary with the signer, community and conversation.
It is therefore too simplistic to say that ASL depends on fingerspelling while BSL reserves it for proper nouns. Classifier or depicting constructions are a separate grammatical resource and should not be presented as BSL’s substitute for fingerspelling.
A practical way to compare the languages
Three small communication tasks reveal more than comparisons of isolated hand pictures:
- Spell a name: ASL normally uses its one-handed alphabet, while BSL uses its two-handed alphabet.
- Ask a question: watch the complete signed utterance. Sign order and non-manual signals matter in both languages, and a written English gloss cannot capture all of them.
- Introduce a topic: both languages can place a topic before a comment, but fluent signers choose structures according to context. This is not a command to put the “largest object” first or the verb last.
These tasks distinguish the manual alphabet, vocabulary and grammar instead of conflating them. For reliable demonstrations, consult specialist video dictionaries and teaching materials. SignBSL gathers regional BSL examples, while Gallaudet University’s ASL Connect provides ASL learning resources. Always check the region, meaning and context attached to an example.
Which language should you learn?
Learn the language used by the people with whom you expect to communicate. BSL will usually be the more relevant choice for someone engaging with Britain’s Deaf community, while ASL will commonly suit someone communicating with ASL users in the United States or parts of Canada.
Geography is only a guide. ASL users live outside North America, and multilingual signers may know several languages. Ask the person or community which language and communication approach they prefer rather than making assumptions.
If your aim is professional interpreting, teaching or support work, a short introductory course is not a professional qualification. Check the competency and registration requirements applying to the role, and seek training led by appropriately qualified Deaf teachers.
Is there a universal sign language?
No natural sign language is universally understood. Different countries and communities use different languages, and some countries have more than one.
International Sign is used in some cross-border settings, including international Deaf events. The WFD International Sign position paper discusses access to interpretation in international settings. International Sign is not a universal replacement for ASL, BSL or other national and community sign languages, and comprehension depends on the participants’ experience and shared context.
Frequently asked questions
Are ASL and BSL the same language?
No. They have different linguistic histories, vocabularies, grammars and manual alphabets. Neither is simply English expressed with the hands.
Can ASL and BSL users understand one another?
Not generally. An occasional sign may appear similar, and experienced signers may negotiate meaning using context or other strategies, but the languages are not mutually intelligible as a rule.
Is ASL one-handed and BSL two-handed?
The description applies to their standard manual alphabets: ASL fingerspelling is predominantly one-handed and BSL fingerspelling is two-handed. It does not mean every ASL lexical sign uses one hand or every BSL sign uses two.
Does BSL always put the topic first and the verb last?
No. BSL can use topic-comment constructions, but sentence structure varies by construction and context. Learners should study complete examples from fluent signers rather than applying one fixed English-to-BSL word order.
Is BSL legally recognised throughout the UK?
Yes, but through different legislation. The British Sign Language Act 2022 recognises BSL in England, Wales and Scotland. In Northern Ireland, BSL and ISL are recognised under the Sign Language Act (Northern Ireland) 2026.
Are sign languages the same in every country?
No. Sign languages develop within communities and are not determined solely by national spoken languages. There can also be several sign languages and many regional varieties within one country.
Is fingerspelling enough to communicate in ASL or BSL?
No. Fingerspelling is one component of each language. Effective communication also requires vocabulary, grammar, non-manual features, receptive skills and an understanding of how signs are used in context.
Key takeaway
The difference between ASL and BSL is not merely one hand versus two. They are separate natural languages shaped by different communities and histories. Their alphabets, conventional signs and grammatical systems differ, so learners should choose the language relevant to their community and learn through qualified Deaf-led or specialist instruction supported by authentic signed examples.
What to Read Next:
- Baby Signing in the UK: BSL-Derived Signs and Practical Tips
- How to Learn BSL: A Beginner-to-Advanced Guide
- British Sign Language for Beginners: A Practical BSL Guide
- Why Is British Sign Language Important?
- How Long Does It Take to Learn BSL? A Practical Study Guide
- Stupid in Sign Language – Video & Image Included
- How Long Does It Take to Learn Sign Language? A Beginner’s Guide