Company: NSP
Filing Date: 2025-08-01
Form Type: S-8
Source: 0001000753-25-000071
Chunk: 0

Company: INSPERITY, INC.
Filing Date: 2025-08-01
Form: S-8
Chunk 0
---
<div align='center'>As filed with the Securities and Exchange Commission on August 1, 2025</div>

#### Registration No. 333-

### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549

#### FORM S-8
<div align='center'>REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933</div>

#### Insperity, Inc.
<div align='center'>(Exact name of registrant as specified in its charter)</div>

| Delaware                                                       
 (State or Other Jurisdiction of Incorporation or Organization) |     | 76-0479645                              
 (I.R.S. Employer Identification Number) |
| 19001 Crescent Springs Drive                                   
 Kingwood, Texas                                                
 (Address of Principal Executive Offices)                       |     | 77339                                   
 (Zip Code)                              |

#### Insperity, Inc. Incentive Plan
<div align='center'>(Full Title of the Plan)</div>

#### Christian P. Callens
<div align='center'>Senior Vice President, Legal, General Counsel and Secretary</div>

#### Insperity, Inc.

#### 19001 Crescent Springs Drive

#### Kingwood, Texas 77339-3802
<div align='center'>(281) 358-8986

(Name, address and telephone number, including area code, of agent for service)

with a copy to:</div>

#### James B. Marshall

#### Baker Botts L.L.P.

#### 910 Louisiana

#### Houston, Texas 77002
<div align='center'>(713) 229-1234</div>

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

| Large accelerated filer |     | þ |     | Accelerated filer         |     | ¨ |
| Non-accelerated filer   |     |   |     | Smaller reporting company |     | ¨ |
|                         |     |   |     | Emerging growth company   |     | ¨ |

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for