Tax Agent Bench · Open Analysis

#	Model	Effort	Score	Cost / task	Harness
1	Fable 5.1	max	49.2%	$13.18	–
2	Opus 5.5	max	45.6%	$15.09	–
3	Opus 5	max	45.5%	$5.14	–
4	Gemini 4	high	44.6%	$3.47	–
5	Wonder Full	max	43.0%	$2.15	–
6	Muse Spark 1.3	max	42.4%	$0.390	–
7	Sonnet 5.5	max	42.0%	$9.25	–
8	GLM 5.3	max	39.7%	$1.80	–
9	Fable 5	max	38.3%	$6.70	–
10	Wonder	max	36.3%	$1.88	–
11	Grok 4.7	xhigh	34.2%	$1.80	–
12	Kimi K3	max	33.4%	$2.79	–
13	Grok 4.6	high	33.1%	$0.978	–
14	Muse Spark 1.2	xhigh	32.8%	$0.269	–
15	Hy4	–	32.6%	$0.585	–
16	MiMo V2.6 Pro	high	32.4%	$0.134	–
17	Gemini 3.8 Flash	high	32.1%	$0.857	–
18	Qwen 3.8 Max	max	32.1%	$1.55	–
19	Haiku 5.5	max	31.9%	$1.16	–
20	GLM 5.3 Flash	max	31.6%	$0.138	–
21	GPT-5.6 Sol	max	31.1%	$7.51	–
22	Ember-1	–	31.1%	$2.97	–
23	Qwen 3.8 27B	xhigh	30.9%	$0.815	–
24	Mistral Large 4	high	30.4%	$2.72	–
25	GPT-5.6 Terra	max	30.0%	$4.83	–
26	Opus 4.8	max	30.0%	$1.69	–
27	Sonnet 5	max	29.4%	$1.79	–
28	MiMo V2.6 Flash	high	28.5%	$0.049	–
29	DeepSeek V4 Flash 0731	high	28.1%	$0.156	–
30	Step 5 Preview	–	27.3%	$0.553	–
31	DeepSeek V4 Pro 0813	max	26.8%	$0.729	–
32	DeepSeek V4.1 Flash	max	26.6%	$0.135	–
33	Sonnet 4.6	max	25.8%	$1.19	–
34	DeepSeek V4	max	25.2%	$0.719	–
35	Grok 4.5	high	24.9%	$0.474	–
36	GPT-5.6 Luna	max	24.8%	$0.465	–
37	Opus 4.7	max	23.7%	$1.27	–
38	Gemini 3.7 Flash	high	22.8%	$0.484	–
39	GPT-5.5	xhigh	21.8%	$4.07	–
40	GPT-6.1 Sol	max	21.8%	$1.32	–
41	Gemini 3.5 Flash	high	21.7%	$0.860	–
42	GPT-6 Astra	max	20.7%	$5.80	–
43	Ling 3.0 Flash Fin	–	20.6%	$0.025	–
44	MiniMax M3	max	20.6%	$0.164	–
45	GPT-6 Luna	max	19.9%	$0.191	–
46	Gemini 3.6 Flash	high	18.0%	$0.356	–
47	Qwen 3.7 Max	max	15.8%	$0.435	–
48	Inkling Small	xhigh	15.4%	$0.092	–
49	Inkling	max	15.3%	$0.354	–
50	GPT-6 Sol	max	15.0%	$2.28	–
51	Kimi K2.6	max	12.4%	$0.566	–
52	Gemini 3 Flash	high	11.8%	$0.101	–
53	MiMo V2.5 Pro	xhigh	11.5%	$0.040	–
54	Qwen 3.7 Plus	high	10.5%	$0.094	–
55	Gemini 3.1 Pro	high	9.3%	$0.302	–
56	GPT-5.4 Mini	xhigh	8.8%	$0.806	–
57	MiMo V2.5	xhigh	7.8%	$0.017	–
58	Qwen 3.6 Plus	max	7.7%	$0.298	–
59	Gemini 3.5 Flash-Lite	high	7.3%	$0.082	–
60	Grok 4.20	xhigh	7.0%	$0.119	–
61	MiniMax M2.7	high	6.9%	$0.120	–
62	Grok 4.3	high	6.2%	$0.117	–
63	Haiku 4.5	xhigh	5.9%	$0.226	–
64	GPT-5.4 Nano	high	5.0%	$0.070	–
65	Mistral Medium 3.5	high	4.5%	$1.44	–
66	Gemini 3.1 Flash-Lite	high	3.1%	$0.014	–
67	Nemotron 3.5 Lightning	–	2.6%	$0.031	–
68	Mercury 2.5	high	2.5%	$0.024	–