CoStar Group (CSGP) Options Chain

NASDAQ: CSGPFinanceReal EstateUSD

29.67-0.14 (-0.47%)

At close: Oct 9, 4:00 PM ET · Delayed 15 min

Expiration date

Expiration: Dec 18, 2026
Days to expiration: 69
Share price: $29.67
Put/call ratio (OI): 1.72
Put/call ratio (volume): 3.00
ATM implied volatility: 57.4%
Expected move: ±$7.40
Open interest (C / P): 9.17K / 15.76K

CSGP options summary

The CSGP options chain for the December 18, 2026 expiration lists 21 call and 15 put contracts, with 69 days until expiration. Open interest stands at 9,167 calls and 15,759 puts, a put/call ratio of 1.72, which is more bearish, with puts outnumbering calls. At-the-money implied volatility near the $30.00 strike is 57.4%, which implies the market expects a move of about ±$7.40 (25.0%) in CoStar Group stock by expiration.

The most open interest sits at the $85.00 call (3.08K contracts) and the $25.00 put (13.61K contracts).

Summary generated from market data by MetaCap's automated system. Methodology

CSGP options chain · December 18, 2026

CSGP calls and puts by strike price. Shaded cells are in the money.
Calls							Puts
OI	Vol	IV	Last	Bid	Ask	Strike	Bid	Ask	Last	IV	Vol	OI
—	—	—	—	—	—	15.00	0.00	0.00	0.01	25.0%	5	0
—	—	—	—	—	—	17.50	0.00	0.60	0.15	85.3%	1	63
3	1	178.0%	8.68	12.20	14.30	20.00	0.05	0.40	0.34	62.7%	1	47
26	1	66.3%	5.90	7.50	8.20	22.50	0.35	0.55	0.45	57.7%	3	145
29	2	65.8%	8.01	5.50	6.50	25.00	0.80	1.05	0.90	55.2%	11	13,610
CSGP $29.67
176	10	58.9%	2.75	2.60	3.20	30.00	2.75	3.40	2.90	55.9%	135	1,310
2,360	2	57.7%	1.25	0.95	1.55	35.00	5.70	6.60	8.69	58.1%	2	299
2,949	2	59.2%	0.60	0.35	0.75	40.00	9.90	11.00	11.90	63.0%	1	230
171	1	62.4%	0.30	0.15	0.40	45.00	0.00	0.00	6.62	—	4	0
94	18	75.1%	0.22	0.05	0.55	50.00	20.80	22.50	17.92	110.8%	6	34
25	2	83.5%	0.05	0.00	0.55	55.00	24.20	26.40	25.60	115.3%	4	0
13	1	70.5%	0.11	0.00	0.10	60.00	29.20	31.40	31.70	125.5%	4	0
12	5	98.2%	0.15	0.00	0.50	65.00	31.30	34.20	32.60	—	1	15
12	3	107.0%	0.10	0.00	0.55	70.00	—	—	—	—	—	—
17	3	111.5%	0.15	0.00	0.50	75.00	44.20	46.50	43.77	80.5%	5	0
18	—	117.4%	0.10	0.00	0.50	80.00	30.70	32.90	22.00	—	—	6
3,085	5	90.6%	0.01	0.00	0.05	85.00	—	—	—	—	—	—
5	2	127.9%	0.06	0.00	0.50	90.00	—	—	—	—	—	—
5	—	158.2%	3.10	0.05	1.30	95.00	—	—	—	—	—	—
162	2	136.9%	0.60	0.00	0.50	100.00	—	—	—	—	—	—
4	—	210.0%	1.50	1.20	2.50	105.00	—	—	—	—	—	—
0	1	50.0%	0.65	0.00	0.00	110.00	—	—	—	—	—	—
1	—	155.0%	0.17	0.00	0.65	115.00	—	—	—	—	—	—

In-the-money callsIn-the-money puts. IV = implied volatility, OI = open interest (contracts). Each contract covers 100 shares. Quotes delayed at least 15 minutes.

Frequently asked questions

What is the CSGP put/call ratio?

For the December 18, 2026 expiration, the CSGP put/call ratio based on open interest is 1.72 (15,759 puts vs 9,167 calls), and 3.00 based on today's volume. A ratio above 1 means more puts than calls.

What is CSGP's implied volatility?

At-the-money implied volatility for CSGP options expiring December 18, 2026 is about 57.4%, an annualized estimate of how much the market expects CoStar Group stock to move.

How many CSGP option expiration dates are there?

CSGP has 10 listed expiration dates, from Oct 16, 2026 to Jan 19, 2029.

What does "in the money" mean?

A call is in the money when the strike price is below the current share price; a put is in the money when the strike is above it. In-the-money contracts have intrinsic value and are shaded in the table.