# Mack Investment Securities, Inc.

> Mack Investment Securities, Inc. is an SEC-registered investment advisory firm in Northfield, IL, registered since 1987, reporting $100 million to $500 million in regulatory assets under management in its Form ADV filing dated March 31, 2026.

- CRD: 17643
- Filed as: MACK INVESTMENT SECURITIES, INC.
- Registration: SEC-registered investment adviser (status as filed: Approved)
- Location: Northfield, IL
- Filing period: October 2026
- Form ADV filing dated: March 31, 2026
- SEC record (IAPD): https://adviserinfo.sec.gov/firm/summary/17643
- AdvisorCensus page: https://advisorcensus.com/firm/mack-investment-securities-inc-northfield-il-17643

## Quick answers

**How is Mack Investment Securities, Inc. compensated?**
On its Form ADV (Item 5.E, October 2026), Mack Investment Securities, Inc. reports these compensation arrangements: a percentage of assets under its management; hourly charges; fixed fees (other than subscription fees); commissions.

**How much does Mack Investment Securities, Inc. charge?**
Its Form ADV Part 2A brochure dated March 31, 2026 states: Flat fee: $2,000 to $8,000 (Financial Planning and Consulting fees); Subscription: $800 to $5,000 a quarter (Financial Planning and Consulting fees); Hourly rate: $300 to $500 an hour (Financial Planning and Consulting fees). Fees can differ by service and may be negotiable; the brochure is the complete statement.

**Where is Mack Investment Securities, Inc. located?**
Mack Investment Securities, Inc.'s principal office is in Northfield, IL, according to its Form ADV; the April 2026 filing also lists 1 other office (Schedule D, Section 1.F).

**Is Mack Investment Securities, Inc. registered with the SEC or a state?**
Mack Investment Securities, Inc. is an SEC-registered investment advisory firm, registered since 1987. Status as filed: Approved. CRD 17643.

**How much does Mack Investment Securities, Inc. manage?**
Mack Investment Securities, Inc. reports $302,589,639 in regulatory assets under management in its Form ADV filing dated March 31, 2026 (71% discretionary).

**How have Mack Investment Securities, Inc.'s assets and staff changed since 2021?**
In the Form ADV data for Mack Investment Securities, Inc.: Regulatory assets under management: $186,261,174 in the October 2021 data and $302,589,639 in the October 2026 data, up 62%. Total employees: 9 in October 2021 and 8 in October 2026. Assets under management move with markets as well as with clients coming and going.

**What types of clients does Mack Investment Securities, Inc. serve?**
By number of clients on Form ADV Item 5.D: individuals (other than high net worth individuals) (379); high net worth individuals (282); pension and profit sharing plans (but not the plan participants or government pension plans) (12).

**Which custodians does Mack Investment Securities, Inc. use?**
Mack Investment Securities, Inc.'s most recent Form ADV filing (Schedule D, Section 5.K(3)) lists Axos Clearing LLC and SEI Private Trust Co. as custodians holding 10% or more of its separately managed account assets.

**Does Mack Investment Securities, Inc. report any disciplinary disclosures?**
Reports no disclosure items on Form ADV Item 11. The detail of any item is on the firm's SEC record: https://adviserinfo.sec.gov/firm/summary/17643

**What changed in Mack Investment Securities, Inc.'s recent Form ADV filings?**
In the April 2026 filing data: Regulatory assets under management went from $263,507,750 to $302,589,639 (+15%).

## From the Form ADV filing

### Compensation (Item 5.E)
- A percentage of assets under your management
- Hourly charges
- Fixed fees (other than subscription fees)
- Commissions

### Fees and minimums (Form ADV Part 2A brochure dated March 31, 2026)

- Flat fee: $2,000 to $8,000 (Financial Planning and Consulting fees)

> As a one -time fixed fee, typically ranging from $2,000 to $8,000, depending on the nature and complexity of each client’s circumstances, payable upon delivery of the financial plan;

- Subscription: $800 to $5,000 a quarter (Financial Planning and Consulting fees)

> As an ongoing fixed fee, typically payable in arrears, typically ranging from $800 to $5,000 per quarter; or

- Hourly rate: $300 to $500 an hour (Financial Planning and Consulting fees)

> On an hourly basis of $300 to $500 per hour, with a two- hour minimum payable upon completion of the plan/project

As stated in the firm's brochure. Fees can differ by service and may be negotiable.

### Custodians (Schedule D, Section 5.K(3))
- Axos Clearing LLC
- SEI Private Trust Co.

Custodians holding 10% or more of the firm's separately managed account assets, as filed on Form ADV (Schedule D, Section 5.K(3)). A custodian holds client assets; it does not endorse or supervise the firm. AdvisorCensus has no relationship with any custodian.

### Regulatory assets under management (Item 5.F)
- Total: $302,589,639
- Discretionary: $214,649,238
- Non-discretionary: $87,940,401

### Clients (Item 5.D)

| Client type | Clients | Assets |
| --- | --- | --- |
| Individuals (other than high net worth individuals) | 379 | $64,994,316 |
| High net worth individuals | 282 | $230,767,875 |
| Pension and profit sharing plans (but not the plan participants or government pension plans) | 12 | $6,827,448 |

### Advisory services (Item 5.G)
- Financial planning services
- Portfolio management for individuals and/or small businesses
- Selection of other advisers (including private fund managers)
- Publication of periodicals or newsletters
- Market timing services

### Firm details
- Registered since: 1987 (39 years)
- Employees: 8 total, 8 performing advisory functions
- Wrap fee program participation: No
- States registered or notice-filed: AZ, CA, CO, FL, IA, IL, IN, LA, MI, MO, MS, OH, TX, WA, WI
- Disclosures (Item 11): Reports no disclosure items on Form ADV Item 11.

### Other offices (Schedule D, Section 1.F), as of the April 2026 filing
- Oak Brook, IL

### Websites listed on Form ADV (Item 1.I)
- [macktracks.com](https://macktracks.com)

## Assets and staff over time

| Data period | Regulatory assets under management | Employees | Filing dated |
| --- | --- | --- | --- |
| October 2021 | $186,261,174 | 9 | March 30, 2021 |
| October 2022 | $200,652,924 | 9 | July 29, 2022 |
| October 2023 | $203,485,844 | 7 | March 31, 2023 |
| October 2024 | $221,655,455 | 7 | May 10, 2024 |
| October 2025 | $263,507,750 | 8 | March 31, 2025 |
| October 2026 | $302,589,639 | 8 | March 31, 2026 |

Regulatory assets under management: $186,261,174 in the October 2021 data and $302,589,639 in the October 2026 data, up 62%.
Total employees: 9 in October 2021 and 8 in October 2026.

## Changes in the filing (last 12 months)

### April 2026
- Regulatory assets under management went from $263,507,750 to $302,589,639 (+15%).

## Source

Form ADV as filed, October 2026. Values appear as filed. Cite as: AdvisorCensus. Mack Investment Securities, Inc. (CRD 17643): Form ADV filing data as of October 2026.