Security deposit interest rules are a quiet compliance trap for landlords and a confusing maze for tenants. These five tools help you calculate what's owed without digging through statutes yourself.
What are Legal Services services?
Security deposit interest is one of the most overlooked landlord-tenant compliance issues in the US. Only a handful of states and cities require landlords to pay interest on deposits, and the rules vary wildly: some set a fixed statutory rate, others tie the rate to a bank index, and a few leave it to the landlord's discretion. For tenants, that means money left on the table at move-out. For landlords, it means potential penalties for underpaying. The tools in this roundup help both sides calculate interest accurately, understand jurisdiction-specific thresholds, and cite the underlying statutes. Most are free, browser-based, and require no signup.
What we looked at when researching Legal Services
We evaluated each tool on four factors: jurisdiction coverage (how many states and cities are supported), rate accuracy and sourcing (whether rates are tied to published statutes or indices), usability (how quickly you can get a result without an account), and scope beyond deposit interest (rent increase limits, late fee caps, notice periods). Each tool brings something different to the table, and the right pick depends on whether you need a quick one-off calculation, a full compliance dashboard, or a property management workflow.
| Provider | Best For |
|---|---|
| RentLateFee.com | Quick one-off deposit interest calculations across 12 states |
| RentByState: Security Deposit Interest, Rent Increase & Late Fee Calculators by State | Statute-cited, multi-jurisdiction calculations with full audit trails |
| Shuk | Landlords already using Shuk's property management platform |
| iManageRent | Property managers who want deposit interest handled inside their management software |
| Berkeley Rent Board | Berkeley tenants and landlords who need the city's official calculation |
A closer look at 5 standout Legal Services
#1 RentLateFee.com
A screenshot of the RentLateFee.com website.
RentLateFee.com offers a free, no-signup security deposit interest calculator that covers 12 states with required interest rules. You select your state, enter the deposit amount and months held, and get the interest owed in seconds. The site publishes a clear state-by-state table showing whether interest is required, the applicable rate, and the return deadline. It's a fast, no-frills tool that works well for a single calculation. The tradeoff is that it focuses narrowly on deposit interest and late fees rather than broader rent regulation.
#2 RentByState: Security Deposit Interest, Rent Increase & Late Fee Calculators by State
A screenshot of the RentByState website.
RentByState goes deeper than any other tool on this list. It covers 16 states and cities for deposit interest, including local ordinances like Chicago's, and applies each year's published rate with a full audit trail. The Connecticut example shows accrued interest broken down by year with the exact statute citation, so you can verify every number. Beyond deposits, it also handles rent increase limits (California AB 1482, Oregon, Washington, NYC, LA, SF, DC), late fee caps, notice periods, and prorated rent. Every rule links to its source, and the site notes sources were re-verified in October 2026. If you need a defensible calculation rather than a rough estimate, this is the tool to use.
#3 Shuk
A screenshot of the Shuk website.
Shuk is a property management platform that includes a security deposit interest calculator among its free rental tools. The calculator is part of a broader suite aimed at independent landlords, covering leasing, screening, payments, and maintenance. If you already use Shuk for rent collection or lease management, the calculator fits naturally into your workflow. The tradeoff is that the tool is embedded in a product ecosystem, so you may need to navigate the platform to reach it. For landlords who want an all-in-one solution, that integration is a feature rather than a bug.
#4 iManageRent
A screenshot of the iManageRent website.
iManageRent offers a security deposit interest calculator as part of its property management toolkit. The tool is designed to calculate interest automatically, reducing manual math for landlords managing multiple units. It sits alongside features like online rent collection, maintenance tracking, and document storage. The calculator is most useful if you're already in the iManageRent ecosystem and want deposit interest handled within your existing workflow. For standalone calculations, simpler tools may get you to an answer faster.
#5 Berkeley Rent Board
A screenshot of the Berkeley Rent Board website.
The Berkeley Rent Board's security deposit interest calculator is a government-run tool specific to Berkeley's Rent Ordinance. It calculates interest owed on deposits for units covered by the ordinance, which applies to fully or partially covered rentals in the city. The tool is authoritative for Berkeley tenants and landlords because it comes directly from the agency that enforces the rules. The obvious limitation is geographic: it only works for Berkeley. But if you're renting in Berkeley, no third-party calculator carries the same weight.
How to choose the right Legal Services
Start with your jurisdiction. If you're in a state with deposit interest requirements, check whether the tool covers your specific state or city. Next, decide whether you need a one-off calculation or an ongoing workflow. For a single move-out calculation, a free standalone tool like RentLateFee.com or RentByState gets you there fast. If you manage multiple properties and want deposit interest handled alongside rent collection and maintenance, a platform like Shuk or iManageRent may fit better. Finally, consider whether you need statute citations. If you're preparing for a dispute or audit, choose a tool that links every number to its legal source. And if you're in Berkeley, go straight to the Rent Board's official calculator.
Expert Conclusion
The right security deposit interest calculator depends on where you rent and how often you need it. RentByState offers the deepest coverage and the strongest sourcing, making it the go-to for anyone who needs a defensible number. RentLateFee.com is the fastest path to a quick answer across 12 states. Shuk and iManageRent make sense if you're already using their platforms. And Berkeley Rent Board remains the authoritative source for Berkeley rentals. Whichever you choose, verify the rate against your state's statute before you rely on the result.