指国务院碳交易主管部门分配给控排企业指定时期内的碳排放额度，是碳排放权的凭证和载体。1单位排放配额相当于1吨二氧化碳当量。配额分配方式：主要分为免费分配与有偿分配。
免费分配：基准法、历史法（历史强度法、历史总量法）有偿分配：拍卖、定价出售 

     由国家发改委根据各地区温室气体排放、经济增长、产业结构、能源结构、控排企业纳入情况等因素确定地区配额总量，并预留部分配额用于有偿分配、市场调节和重大项目建设。     地方配额在初期以免费分配为主，适时引入有偿分配，并逐步提高比例。其中免费分配的标准和方法由国家发改委参考相关行业主管部门的意见统一确定。  地方配额总量与免费分配配额之间的轧差，可由地方政府用于有偿分配，有偿分配的具体方式由地方确定。
1、历史总量法：配额分配以企业过去的碳排放数据为依据。一般选取企业过去3-5年的碳排放量得出该企业的年均历史排放量，而这一数字就是企业下一年度的排放配额。历史法对数据的要求较为简单， 操作容易，因此各试点的免费配额分配以历史排放量或历史强度法为主。但历史法假设企业的碳排放会一直按照过去的轨迹进行下去， 从而忽略了两个方面的因素：
一是在碳市场开始之前企业已经采取的减排行动
二是在碳市场开始之后，企业还有可能在市场机制的影响下改变行为，进一步进行减排
因此，历史法可能会“鞭打快牛”，不利于激励企业今后对节能减排技术的研发和引进。
2、历史强度法：
以企业历史碳排放为基础配额，并在其后乘以多项调整因子，将前期减排奖励、减排潜力、对清洁技术的鼓励、行业增长趋势等因素考虑在内，可在一定程度上弥补历史法的缺陷。
3、基准线法：
基于“最佳实践”原则，就是将不同企业（设施）同种产品的单位产品碳排放由小到大进行排序，选择其中前10%（不固定，也可选30%或行业平均值）作为基准线。
Refers to the carbon emission quota allocated by the competent department of carbon trading under The State Council to control and discharge enterprises within a specified period, which is the certificate and carrier of carbon emission right. One unit of emission quota is equivalent to one tonne of carbon dioxide equivalent.Quota distribution: mainly divided into free distribution and paid distribution.

Free distribution: benchmark method, historical method (historical intensity method, historical total method) paid distribution: auction, pricing sale

The National Development and Reform Commission will determine the total amount of regional quotas based on factors such as greenhouse gas emissions, economic growth, industrial structure, energy structure and the inclusion of emission control enterprises in each region, and reserve part of the quotas for paid distribution, market adjustment and major project construction. Local quotas will be mainly distributed free of charge in the initial stage, and paid distribution will be introduced in due time, and the proportion will be gradually increased. The standard and method of free distribution shall be determined by the National Development and Reform Commission with reference to the opinions of relevant industry authorities. The difference between the total amount of local quotas and the quotas allocated free of charge may be used by local governments for compensated distribution. The specific method of compensated distribution shall be determined by local governments.

1. Historical aggregate method: Quota allocation is based on the past carbon emission data of enterprises.Generally, the annual average historical emissions of the enterprise are obtained by selecting the carbon emissions of the enterprise in the past 3-5 years, and this figure is the emission quota of the enterprise in the next year. The historical method requires relatively simple data and is easy to operate, so the free quota allocation of each pilot is mainly based on the historical emission or historical intensity method. However, the historical method assumes that companies' carbon emissions will continue in the same way as in the past, which ignores two factors:

The first is the actions taken by companies to reduce emissions before the carbon market began

Second, after the start of the carbon market, enterprises may change their behaviors under the influence of the market mechanism to further reduce emissions

Therefore, the historical law may "whip the fast cow", which is not conducive to encouraging enterprises to develop and introduce energy-saving and emission reduction technologies in the future.

2. Historical intensity method:

Based on the historical carbon emissions of enterprises, the quota is multiplied by a number of adjustment factors, and factors such as early emission reduction incentive, emission reduction potential, encouragement of clean technology, and industry growth trend are taken into account, which can make up for the shortcomings of the historical method to a certain extent.

3. Base line method:

Based on the principle of "best practice", the carbon emission per unit product of the same product of different enterprises (facilities) is ranked from small to large, and the top 10% (not fixed, can also choose 30% or industry average) is chosen as the baseline.