Old Second National Bank savings, CD and money market rates
Old Second National Bank advertises up to 0.05% APY on its O2 Money Builder Savings account. The 0.05% needs a balance of at least $50,000. Below that, the account advertises 0.02%.
On a $10,000 balance the account earns 0.02% overall, about $2 in a year, which is 0.35 percentage points below the national savings average of 0.37% (FDIC, Sep 2026).
Ranked #1702 of 1929 tracked savings rates by advertised APY. For a $10,000 balance it would rank #1808.
Estimate your earnings·What Old Second National Bank actually pays
Old Second National Bank at a glance
| Savings | |
|---|---|
| Top savings APY | Up to 0.05% · O2 Money Builder Savings · needs at least $50,000 |
| Minimum to open | $1,000 · O2 Money Builder Savings |
| Against the national average | 0.32 percentage points below the 0.37% FDIC savings average (Sep 2026) |
| CDs | |
| Top CD APY | 3.50% · 8 months · CD Special 8 Month |
| Minimum to open | $1,000 · 8 months CD |
| Money market | |
| Top money market APY | Up to 0.25% · O2 Money Manager Money Market · needs at least $100,000 |
| Minimum to open | $5,000 · O2 Money Manager Money Market |
| Against the national average | 0.38 percentage points below the 0.63% FDIC money market average (Sep 2026) |
| FDIC certificate | 3603 · Aurora, IL |
|---|---|
| Website | www.oldsecond.com |
| Branches | 57 branches in IL |
| Availability | Available in IL |
Old Second National Bank savings, CD and money market rates
How the rate applies
How the rate applies
Rates are APY. The national savings average is 0.37% (FDIC, Sep 2026). The top tracked savings rate on Banksparency is 5.50%. Across 59 savings accounts from 58 banks in the Banksparency core savings index, the median advertised rate is 3.65%, and one account in ten advertises 4.01% or more. See the highest savings rates.
Old Second National Bank CD rates
| Term | APY | Minimum | Product |
|---|---|---|---|
| 3-11 months | 0.05% | not stated | 3 - 11 Month CD |
| 6 months | 3.50% | $1,000 | CD Special 6 Month |
| 8 months | 3.50% | $1,000 | CD Special 8 Month |
| 11 months | 3.25% | $1,000 | CD Special 11 Month |
| 12-29 months | 0.10% | not stated | 12 - 29 Month CD |
| 30-35 months | 0.15% | not stated | 30 - 35 Month CD |
| 36-59 months | 0.20% | not stated | 36 - 59 Month CD |
| 60 months | 0.25% | not stated | 60 Month CD |
Interactive Tool
Calculate Savings for Old Second National Bank
All calculations are based on APY.
Savings Breakdown
- Interest Earned+$7.50(0.1%)
- Total Contributions$13,000
- Initial Deposit$1,000
Projected Balance
$14,007.50
The Banksparency Savings Calculator provides estimated savings growth based on user input and our latest data.
What Old Second National Bank pays on deposits
FDIC call report data
An advertised rate tells you what a new savings account earns today. It cannot tell you how the bank has priced the savings and money market deposits it already holds, over time. This section shows that. The figure is computed from the interest expense and deposit balances that every bank files with the FDIC in the same form. That is what makes it comparable across banks and across quarters.
The two figures answer different questions, so they sit side by side and are not combined. The 0.05% needs a balance of at least $50,000. Below that, the account advertises 0.02%.
In Q2 2026, Old Second National Bank paid a higher average rate on savings and money market deposits than 43% of banks that reported a figure (FDIC call report). The all-bank median was 1.45%.
- Old Second National Bank, savings and money market
- All-bank median
How to read these figures
What the average covers. It is an average across the whole bank, taken from its own quarterly FDIC call report. It covers savings accounts and money market deposit accounts, personal and business, at every balance tier. It also covers accounts that were opened years ago and keep the rate of those years. The FDIC line does not separate consumer accounts.
The second figure. The scale row also shows the average across all interest-bearing deposits: savings, interest checking, money market accounts, CDs, personal and business. That figure covers the whole deposit book. The two are shown separately and are not combined.
What the advertised rate covers. It is the rate that this bank advertises now for a new savings account. Banksparency records it from the bank's website on the date shown beside it.
Why the two differ. They measure different things, so this page shows them side by side and keeps them apart. An advertised rate applies to one account, opened now, at today's price. The average also includes older savings balances at the rates of earlier years, money market balances that were priced in a different rate environment, and business accounts. An average below an advertised rate is the usual result of that arithmetic. On its own it is not evidence about the account that you would open.
What the average is useful for. The bank files the data itself, under reporting instructions that are the same for every filer, and the same computation runs for every bank on this site. That makes it comparable in a way that an advertisement is not. Two things on this page read it: the percentile, which shows where the quarter sits among all filers, and the chart, which shows the direction the figure has moved across quarters.
What the average cannot tell you. It cannot tell you the rate that you would earn. No single customer earns the average. For your rate, read the advertised rate above and the rate tables on this page, each with the date it was observed.
What to do next. Use the advertised rate to work out what a new account earns. Use the chart to see how the quarterly average has moved against the all-bank median. Then compare the advertised rate against the current rates on the savings-rate tables before you open an account.
Definitions: Call Report · Rate Paid on Deposits · Interest-Bearing Deposits · Front Book and Back Book · Deposit Rate Percentile
Average annualized rates paid on savings and money market deposits, and on all interest-bearing deposits, quarterly. The FDIC line for savings includes money market deposit accounts and business savings deposits and does not separate consumer accounts. Source: FDIC call report data, as reported; it may be amended. The percentile compares all FDIC filers, count-weighted. A missing quarter is suppressed, never interpolated. The percentile counts the banks that paid strictly less on savings and money market deposits, one vote per bank, among the banks that reported a figure for the quarter.
So what is the catch?
| Product | APY | Min to open | Min to earn | Balance cap | Monthly fee | Requirements | Rate type | 12-mo trend |
|---|---|---|---|---|---|---|---|---|
| O2 Money Builder Savings | 0.05% | $1,000 | $1,000 | None | not stated | None | Tiered | |
| Junior Savers | 0.02% | $10 | $0 | None | not stated | None | One rate | |
| Regular Savings | 0.02% | $250 | $0 | None | not stated | None | One rate | |
| O2 Money Manager Money Market | 0.25% | $5,000 | $5,000 | None | not stated | None | Tiered |
Rate type: one rate applies at every balance. A tiered rate changes with your balance. A promotional rate changes after the period shown. A balance cap is the largest balance the highest rate applies to.
The 12-month trend shows the highest advertised rate observed each day and includes promotional tiers where one applied.
CDs
| Product | Term | APY | Min to open | Early withdrawal fee | Compounding |
|---|---|---|---|---|---|
| 3 - 11 Month CD | 3-11 months | 0.05% | not stated | not stated | not stated |
| CD Special 6 Month | 6 months | 3.50% | $1,000 | not stated | not stated |
| CD Special 8 Month | 8 months | 3.50% | $1,000 | not stated | not stated |
| CD Special 11 Month | 11 months | 3.25% | $1,000 | not stated | not stated |
| 12 - 29 Month CD | 12-29 months | 0.10% | not stated | not stated | not stated |
| 30 - 35 Month CD | 30-35 months | 0.15% | not stated | not stated | not stated |
| 36 - 59 Month CD | 36-59 months | 0.20% | not stated | not stated | not stated |
| 60 Month CD | 60 months | 0.25% | not stated | not stated | not stated |
Opening and using the account
| Availability | Available in IL |
|---|---|
| Footprint | 57 branches in IL |
| Eligibility | not stated |
How Old Second National Bank behaves over time
Every observation of the advertised O2 Money Builder Savings rate in the last 12 months was 0.05% (observed through Sep 16, 2026). The series includes promotional tiers where one applied.
- O2 Money Builder Savings
- The same as 7 days ago.
- 8 months CD
- The same as 7 days ago.
- O2 Money Manager Money Market
- The same as 7 days ago.
- Rate last changed
- Sep 1, 2026(effective date)
$10,000 at the 0.05% APY Old Second National Bank advertises on O2 Money Builder Savings grows to $10,005 in a year. Prices rose 3.4% in the year to August 2026 (Consumer Price Index (CPI)). After a year of prices rising at that pace, it buys as much as $9,676 does today. See how the federal funds rate shapes savings rates.
Old Second National Bank CD rates over time
Who is Old Second National Bank?
| Headquarters | Aurora, IL |
|---|---|
| Founded | 1887 |
| Scale | $6.9B assets · $5.5B deposits, $3.7B of it interest-bearing (Q2 2026, FDIC) |
| Deposit insurance | FDIC insured · Certificate 3603 |
Financial detail is in What Old Second National Bank pays on deposits above.
Common questions about Old Second National Bank
Is Old Second National Bank FDIC insured?
Yes. Old Second National Bank is FDIC insured under certificate 3603, so deposits are covered up to $250,000 per depositor, per ownership category.
What is the minimum deposit at Old Second National Bank?
Old Second National Bank requires a minimum deposit of $1,000 to open its O2 Money Builder Savings account, as observed on Sep 16, 2026. Check the bank's current terms before you open an account.
Does the 0.05% apply to my whole balance?
The 0.05% needs a balance of at least $50,000. Below that, the account advertises 0.02%. Rates are as observed on Sep 16, 2026.
Does Old Second National Bank have branches?
Yes. Old Second National Bank operates 57 branches according to FDIC branch records, in addition to its website and mobile apps.
Old Second National Bank against its closest alternatives
| Bank | Savings APY | Rate paid on savings and money market deposits (Q2 2026) | Min deposit | Branches |
|---|---|---|---|---|
| Old Second National Bank | 0.25% | 1.28% | $5,000 | 57 branches in IL |
| Arrow Bank National Association | 0.05% | 2.21% | $500 | 57 branches in NY |
| Bankesb | 0.30% | 1.34% | $1,000 | 56 branches in CT, MA, NH |
| Bankhometown | 0.30% | 1.06% | $1,000 | 15 branches in CT, MA |
Alternatives are the three tracked banks whose highest savings APY is closest to Old Second National Bank's.
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Rate hubs: today's highest savings rates, CD rates by term, and money market rates.