For current ACT testing, Science is optional and does not affect the Composite score.

The Composite is based on:

• English;
• Math;
• Reading.

So why would anyone still take Science?

Because “optional for the Composite” is not identical to “useless.”

The right answer depends on:

• colleges/programs;
• STEM goals;
• your Science strength;
• testing fatigue;
• available preparation time.

What happens if you take Science?

You receive a separate Science score on the 1–36 scale.

ACT also reports STEM-related information for students who take the relevant sections.

Science can therefore provide an additional college-reportable signal.

What happens if you skip Science?

Your Composite is still calculated from English, Math, and Reading.

You are not “missing” one-fourth of the Composite under the current scoring model.

That is a major change from the legacy ACT. See our Enhanced ACT guide for the full rundown of what changed.

Strong reasons to consider Science

1. A target program explicitly recommends or requires it

This is the strongest reason.

Admissions policies can differ by:

• institution;
• engineering school;
• honors program;
• scholarship;
• country.

Check the current official college/program page.

Do not rely on an old forum post.

2. Science is a genuine strength

If you routinely score very well on ACT Science, the score may add useful information.

Especially if you are presenting a STEM-oriented academic profile.

3. You want a STEM score/data point

If a program values quantitative/scientific evidence, taking Science can give it another standardized metric.

This does not mean every STEM applicant needs Science.

It means it can be strategically useful in some cases.

Good reasons to skip Science

1. Your target colleges do not use it meaningfully

If no program on your list requires/recommends it and the score adds little, skipping may be rational.

2. It creates fatigue that hurts your prep priorities

Science adds 40 minutes of testing.

Preparation also consumes time.

If Math is currently 24 and Science is 30, it may be more valuable to spend extra study hours raising Math because Math affects the Composite.

3. Science is a major weakness with little strategic upside

Do not take an optional section out of fear if it adds no application value.

A decision matrix

International students

International students should be especially careful because:

• institution policies vary;
• international ACT administration details differ;
• some universities outside the US may interpret testing differently.

Check the institution receiving the score.

Do not assume an optional US admissions convention applies globally. Browse the rest of our ACT guides for more section-specific decisions.

Does skipping Science make your ACT look incomplete?

Under the current ACT structure, Science is an optional add-on.

A core ACT is a legitimate current ACT result.

But individual institutions can choose what they value.

That is why your decision should be college-list driven.

Can a strong Science score compensate for a weak Composite?

Not directly.

Because Science is not part of the Composite.

A strong Science score can be an additional positive signal, but it does not mathematically raise your Composite.

Example

Student A:

• English 29
• Math 31
• Reading 30
• Composite = 30
• Science 34

Student B:

• English 29
• Math 31
• Reading 30
• Composite = 30
• no Science

Their core Composite is the same.

Student A has an additional Science data point.

Whether that extra data matters depends on the receiver.

Prep-time economics

Suppose you have 20 hours before your test.

Option 1:

• 8 hours Science
• 12 hours core sections

Option 2:

• 20 hours core sections

If Science is optional and your core score needs improvement, Option 2 may produce more admissions value.

If Science is required/recommended and you already have strong core scores, Option 1 may make more sense. If you're working to raise your core Composite specifically, our ACT 20 to 25 study plan covers the highest-value skills for that range.

Questions to answer before registering

1. Does any target college require Science?
2. Does any target program recommend it?
3. Does Science contribute to a scholarship requirement?
4. What are my current Science practice scores?
5. Is Science stronger than my core sections?
6. Will adding Science create significant fatigue?
7. Do I have enough time to prepare?

If you cannot answer questions 1–3, research them before paying for the option. If your core Composite still needs work, our should you retake the ACT guide can help you decide where to focus first.

FAQ

Is ACT Science optional?

Yes for current ACT national testing.

Does Science count in the Composite?

No. The current Composite uses English, Math, and Reading.

Is ACT Science still scored?

Yes. If you take it, you receive a Science score.

Should STEM applicants take Science?

Not automatically. Check the specific colleges/programs and consider whether the score strengthens your profile.

Is Science mostly memorization?

No. ACT emphasizes data interpretation, experimental design, and evaluation of scientific arguments/models, with some introductory science knowledge potentially useful.

Does the SAT have a separate Science section?

No.

Bottom line

Take ACT Science because it has a specific strategic purpose, not because the legacy ACT used to require it.

If no target institution cares and your core Composite can improve, prioritize the core.

If a program values Science and you are strong at it, the additional section can be worth taking.

Official references

• ACT test overview: https://www.act.org/content/act/en/products-and-services/the-act.html
• ACT enhanced FAQs: https://www.act.org/content/act/en/products-and-services/the-act-educator/the-act-test/enhancements-k12/faqs.html
• ACT Science description: https://www.act.org/content/act/en/products-and-services/the-act/test-preparation/description-of-science-test.html

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