Advanced Higher Biology grade boundaries 2025: what A to D needed

Advanced Higher Biology grade boundaries 2025

The table is built from SQA's Grade boundaries 2025 workbook (released 5 August 2025). The 2025 course report for Advanced Higher Biology lists identical minimum marks.

Biology is graded on the total of two components, a question paper and an investigative project, out of 160. The question paper has a multiple-choice Section 1 and a structured-response Section 2. For topics, see the Advanced Higher Biology guide.

Working out a grade: 77 out of 160

A candidate's question paper and project come to 77. That is at least 69, so it clears the C line, and below 84, so it misses the B line. The grade is a C. The candidate is 8 marks above the C boundary, 7 short of a B and 23 short of an A. Seventy-seven is 48% of 160, while the C line is at 43%.

Check the arithmetic with SQA's rule. C is 69 and A is 100, so the gap is 31, and B = 69 + ⌊(2 × 31 + 1) ÷ 4⌋ = 84 and D = 69 − ⌈(2 × 31 − 1) ÷ 4⌉ = 53.

Biology 2025 against 2024

The report describes Section 1 as performing as expected and Section 2 as more challenging than expected, and says that was taken into account in the boundaries. The shares moved accordingly: the A line went from 65% to 63% of the total and the B line from 54% to 53%. The D boundary stayed at 53 and the upper A at 130.

Advanced Higher Biology boundaries since 2019

The maximum was 120 up to 2023 and 160 from 2024, so compare shares. In 2019 an A needed 63% of the total, in 2022 and 2023 it needed 60% and 68%, and in 2025 it needed 63%.

Who sat it and how they did

The report counts 3,125 resulted entries, up from 2,999 in 2024, before appeals were complete.

Biology had the lowest A rate of the three Advanced Higher sciences, at 17.2%, and the highest No Award rate, at 14.5%. More candidates got a C than any other grade.

What the 2025 report says candidates found hard

• Unfamiliar contexts. Candidates did less well when applying knowledge to new situations, in investigative biology and in drawing conclusions from tables and graphs.
• Qualitative data. In question 10 of Section 1, few saw that a score assigned by observation, such as red wing area, is qualitative because it cannot be ranked numerically.
• Blank or control. In 2(b) some candidates called the blank in colorimetry a negative control and lost the mark.
• Literacy. Markers noted that some candidates had trouble expressing themselves clearly and concisely, and missed marks as a result.
• Choice question. Question 12 offered meiosis or plasmodium. Meiosis was more popular, but the mean mark for both options was similar.
• Similar projects. Markers noted more centres where several candidates did very similar projects, often with the same aim, which the assessment conditions forbid.

Put today's paper next to the table

Today's Advanced Higher Biology paper is a short timed paper of 8 questions and 25 to 35 marks. Mark it with the worked answers once they appear and convert to a percentage. The 2025 A line was 63% of the total and the C line 43%. As the paper has no project, a good result says little about the project side.

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Scotland · Advanced HigherAdvanced Higher Biology grade boundaries 2026Qualifications Scotland's 2026 Advanced Higher Biology boundaries out of 160: A at 98, C at 69. How they changed from 2025 and what the report says.