How we source, calculate, and publish our data

Summary

• We republish what sources report. Rates and yields are shown as the fund manager, bank, Central Bank of Kenya or exchange published them. We do not recompute, smooth or adjust them.
• What we calculate is limited and stated below. Index averages, after-tax figures, rankings and calculator outputs are Serrari calculations. Each one is defined on this page.
• Every table shows its own date. Sources publish on different schedules. Each page shows the date of the data it displays, and fixed-deposit rows show the date each bank's rate was last checked.
• Serrari is a comparison publisher. We do not manage funds, take deposits or issue securities, and nothing here is investment advice.

Who produces this data

The same three people stand behind every dataset on this site: the money market fund indexes, the Treasury bill series and the fixed deposit index.

Montel Kamau — Financial Analyst

Defines what each figure means and signs off the index definitions, the after-tax treatment and the limitations published for every series.

Rosemary Wambui — Data Analyst

Checks each published figure against the fund manager, bank, Central Bank of Kenya or exchange disclosure it came from, and records the date of every check.

David Kabera — Data Engineer

Builds and runs the collection, transformation and serving pipeline behind every figure on these pages.

Serrari is a comparison publisher, not a fund manager, bank or broker. None of the people above is remunerated by any provider listed on this site.

Money market funds (MMFs)

Source

Serrari analysts record the annual yield each fund manager publishes for its KES and USD money market funds. KES and USD funds are tracked as separate series. Assets under management (AUM) come from the most recent Capital Markets Authority quarterly report we hold. That is Q4 2025 at the time of writing, so AUM figures can be several months old.

Which funds are covered

Rates are recorded daily from the figures fund managers publish. Every rate in a table carries the same record date; a fund with no figure for that date is left out of the table rather than shown with an older one, so the count can vary from day to day.

What we publish for each fund

• Yield: the annual yield announced by the manager, used as announced. Serrari does not convert or compound it.
• Net yield: the announced yield less 15% withholding tax, calculated as yield × (1 − 0.15).
• Management fee and minimum investment: as stated by the manager.
• Rank: funds are ordered by yield, highest first. Funds with the same yield share a rank.

Serrari Kenya MMF Average Index

The simple (equal-weighted) average of the latest recorded yield of every fund in the series on the most recent data date:

Average Index = (y₁ + y₂ + … + yₙ) ÷ n

Each fund counts equally, whatever its size. It is calculated separately for KES and USD funds, and n is shown on the page as the number of funds tracked. The live value is on Kenya money market fund rates and USD money market funds.

Serrari Kenya MMF Leaders Index

The Leaders Index is designed to track the funds that have stayed at the top of the table, not the funds that led on a single day. Its definition, adopted on 21 September 2026, is:

1. The index has five member funds, chosen on the 1st of every month.
2. A fund qualifies if it ranked in the top five by yield on every recorded day of the previous three months. A day on which the fund did not report does not count against it.
3. If fewer than five funds qualify, the remaining places go to the funds with the highest average yield over the same three months. A tie for the last place goes to the higher three-month average.
4. Membership is fixed until the next 1st. The published value is the simple average of the five members’ latest yields, updated daily.
5. A member that stops reporting keeps its last yield in the average, and is flagged as stale if it has not reported for more than 14 days.
6. KES and USD funds are calculated separately under the same rules.

Being implemented. Until this definition is live in our data pipeline, the Leaders Index figure on our pages, and its published history, is the simple average of the five highest yields in the latest data, with members that can change daily. This page will record the date the new rules take effect.

Published history

Serrari's published MMF index history begins on 18 September 2025. It was weekly until October 2025 and has been recorded on most business days since, with some gaps. We do not publish figures for dates before that, and we do not fill gaps.

Limitations

• Managers publish on their own schedules, so on a given date some funds may show an earlier figure than others.
• An announced yield describes recent performance. It is not a forecast, and your actual return will differ.
• The index covers the funds Serrari tracks. It is not a register of every fund licensed by the CMA.

Treasury bills and bonds

Sources

• Treasury bills: results of the Central Bank of Kenya's weekly auctions, entered by Serrari analysts after CBK publishes them. One row per auction, with the rate for each tenor offered (91, 182 and 364 days). The 364-day paper is not offered every week.
• Treasury and infrastructure bonds: a bond sheet maintained by Serrari analysts with each issue's ISIN, coupon, maturity, price and yield to maturity.

What we publish

• T-bill rates: the latest weighted-average accepted rate from CBK's auction for each tenor, shown with that auction's date. Tenors can carry different dates because the 364-day bill is not offered every week.
• T-bill history: for each tenor, the simple average of the auction rates recorded in each month, for the past twelve months. Serrari holds CBK results back to April 2024; the site currently publishes the most recent twelve months.
• Bond yields: the yield to maturity recorded for each issue on the sheet's latest date.
• Calculator outputs: returns worked out from the auction or sheet rate. Each calculator states the tax treatment it applies.

Limitations

Bond prices and yields are indicative, not executable quotes. The price a broker or bank offers you will depend on the size of the trade and on liquidity.

Fixed deposits

Source

Most Kenyan banks do not publish fixed deposit rates online, so Serrari checks them bank by bank, from the bank's own website where it publishes rates and by phone where it does not. Every row on fixed deposit rates in Kenya shows the date that bank was last checked. Different banks are therefore checked on different dates.

What we publish

• Rate: the rate the bank quoted for the tenor. Where the bank quotes a tiered, ranged or negotiable rate, we show the top of the range marked “up to”.
• After tax: the rate less 15% withholding tax.
• Banks that would not quote a rate still appear, marked “On request”. We do not leave a bank out because it has no published rate.

The Serrari Fixed Deposit Index

The index is the simple average of each bank's best published rate, divided by the number of banks that publish one. One figure per bank: a bank that quotes four terms does not count four times against a bank that quotes one. It is published separately for KES and USD deposits under the same rules, on fixed deposit rates in Kenya and USD fixed deposit rates.

• A bank enters the index once it publishes or quotes a rate for any tenor. Its best rate is the highest of those.
• Where that rate is tiered, ranged or negotiable, the top of the range is used and the published index reads “up to” — the same rule as the table.
• Banks that quote only on request are tracked and named on the page, but cannot enter the average.
• The index is stated before tax. Fixed deposit interest is taxed at 15% withholding tax at source.
• It is dated with the most recent bank check behind it, not with today's date. Fixed deposit rates move slowly and each bank is checked on its own date.

Limitations

Fixed deposit rates are negotiated and change without notice. Confirm the rate with the bank before you deposit. The index describes what banks publish, not what a large depositor could negotiate, and it is an unweighted average of banks rather than of deposits: it does not reflect how much money sits at each bank.

Treasury bonds

Source

Government bond terms — issue number, coupon, maturity date and whether the issue is an infrastructure bond — come from the Central Bank of Kenya prospectus for each issue. Corporate bonds listed on the Nairobi Securities Exchange are shown alongside them, with terms from the exchange listing. Yield to maturity is computed from the traded price. The average yield quoted in the citation covers the government bonds only.

What we publish

• Yield to maturity: the annual return if the bond is held to maturity at the current price.
• Coupon: the rate the issue pays on its face value, as the prospectus states it.
• Tax: withholding tax on government bonds follows the bond’s original term — 10% over ten years, 15% at ten years or under. Infrastructure bonds are exempt, and are marked as such.

Limitations

Yield to maturity moves with the traded price, so the figure is a snapshot rather than a promise. Serrari does not licence exchange price data, so bond prices are shown only where the exchange publishes them.

Unit trusts

Source

Each fund manager announces its own yield. Serrari republishes what the manager announced, for every CMA-regulated unit trust it tracks, split into fixed income, balanced and equity.

What we publish

• Annual yield: exactly as announced. Serrari does not recompute, compound or smooth it.
• Before tax: the yield shown is before the 15% withholding tax. No after-tax figure is published for unit trusts.
• Fee, minimum and NAV: as the manager publishes them.

Limitations

Balanced and equity funds are quoted on a unit price rather than a yield, so a single headline rate compares them badly. Read the category before comparing two funds, and treat a past yield as a record rather than a forecast.

Savings accounts

Source

Rates are taken from each bank’s or mobile-money provider’s own published terms and recorded with the date of the check.

What we publish

• Rate: the published annual interest rate, and the rate after 15% withholding tax.
• Minimum balance, where the provider publishes one. Monthly fees are not in the table; check the provider’s tariff, because a fee can outweigh the interest on a small balance.
• The CBK benchmark rate is shown for reference and is not counted as a product.
• Deposits are insured by the KDIC up to KES 500,000 per depositor per institution.

Limitations

Savings rates change rarely and are not fed live, so the date on the page is the date of the last check and may be several weeks old. Tiered accounts pay the published rate only above a stated balance. Confirm with the provider before moving money.

Stock exchanges

Sources

• JSE and EGX: index and share data from Yahoo Finance. The JSE figure is the FTSE/JSE Top 40 index. The EGX figure is the EGX 30.
• NGX: index data from the Trading Economics public API.
• Nairobi Securities Exchange: Serrari does not hold an NSE market-data licence and does not show NSE share prices. The NSE page republishes the headline figures from the exchange's own published market statistics summary (index levels and turnover), with the exchange's date.

Limitations

Third-party feeds can be delayed or incomplete. A field we could not fill shows “—” rather than an older value.

What we do not do

• We do not interpolate or estimate missing data.
• We do not publish figures we cannot trace to a source named on this page.
• We do not accept payment for a fund's or bank's position in a rate ranking.
• We do not give investment advice. This page explains how a number is produced, not whether to act on it.

Definitions

The Serrari Market Data Glossary: the terms used on our data pages, each linked to the section above that explains how the figure is produced.

Serrari Kenya MMF Average Index

The simple, equal-weighted average of the latest recorded annual yield of every money market fund Serrari tracks, on the most recent data date: (y1 + y2 + ... + yn) / n. Each fund counts equally whatever its size, and the index is calculated separately for KES and USD funds. How it is produced

Serrari Kenya MMF Leaders Index

A five-member index of the money market funds that have stayed at the top of the table rather than led on a single day. Members are chosen on the 1st of each month from funds that ranked in the top five by yield on every recorded day of the previous three months, and membership is fixed until the next 1st. Adopted 2026-09-21. Not yet live in the data pipeline: the figure currently published is the simple average of the five highest yields in the latest data, with members that can change daily. How it is produced

Serrari Fixed Deposit Index

The simple average of each Kenyan bank’s best published fixed deposit rate, divided by the number of banks that publish one. One figure per bank, so a bank quoting four terms does not outweigh a bank quoting one. Stated before tax, dated with the most recent bank check behind it, and published separately for KES and USD deposits. How it is produced

Announced annual yield

The annual yield a fund manager announces for its fund, republished by Serrari exactly as announced. Serrari does not recompute, compound, smooth or adjust it. It describes recent performance and is not a forecast. How it is produced

Yield after withholding tax

A published rate less the 15% withholding tax deducted at source in Kenya on money market fund, Treasury bill and fixed deposit interest. Shown alongside the gross rate so the two are never confused. Among Kenyan government paper, only infrastructure bonds are exempt from this tax. How it is produced

Weighted-average accepted rate

The rate the Central Bank of Kenya publishes after a Treasury bill auction: the average rate across the bids it accepted, weighted by the amount accepted at each. Serrari republishes it per tenor with that auction’s own date, because the 364-day bill is not offered every week. How it is produced

“Up to” rate

How Serrari marks a rate a bank quotes as tiered, ranged or negotiable. The top of the range is shown, labelled “up to”, and that same top-of-range figure is what enters the Fixed Deposit Index. It is the best case the bank advertises, not a rate every depositor will get. How it is produced

Last checked date

The date Serrari last verified a bank’s fixed deposit rate with that bank, from its published rates or by phone. Because most Kenyan banks do not publish fixed deposit rates online, each bank carries its own check date rather than a single site-wide date. How it is produced

Stale fund

A fund that has not reported a new yield for more than 14 days. It keeps its last reported yield in the index average and is flagged as stale, rather than being dropped or having a figure estimated for it. How it is produced

Data date

The date of the data a table displays, as opposed to the date the page was generated. Sources publish on different schedules, so every Serrari table shows its own data date and no figure is presented as more current than its source. How it is produced

How to cite Serrari data

You are welcome to quote Serrari figures in articles, research and teaching, under the terms for using Serrari data below. Please name Serrari Group, link to the page the figure came from, and give the date shown on that page, since most of these figures change daily or weekly:

Source: Serrari Group (serrarigroup.com), <dataset name>, as of <date>.

For example:

Source: Serrari Group (serrarigroup.com/ke/mmf), Serrari Kenya KES MMF Average Index, as of 18 September 2026.

For fixed deposits, give the bank's “last checked” date rather than the date you read the page. Figures that Serrari republishes from the CBK, the NSE or a fund manager remain those organisations' data. Cite them as the original source as well.

Using Serrari data

Serrari Group's own data is © Serrari Group. That covers the Serrari Kenya MMF Average Index and Leaders Index, our rankings, our compiled comparison tables and our after-tax figures.

You may, free of charge

• quote individual figures, and short extracts from our tables, in news reporting, research, teaching, commentary and AI-generated answers;
• embed official Serrari widgets, unmodified, as we provide them.

Every use must name Serrari Group as the source, link to the page the figure came from, and give the date shown on that page.

You need our written permission to

• copy, scrape or download our tables or history in bulk, or by automated means;
• republish, resell or redistribute our data as a dataset, feed, API or product;
• use our data to build a competing comparison service or index;
• change our figures while still attributing them to Serrari.

Figures we republish from fund managers, the Central Bank of Kenya or the Nairobi Securities Exchange remain those organisations' data and are subject to their terms. Our data is provided for information only, without warranty; see our Terms and Conditions.

For API access, bulk data or other licensing, contact info@serrarigroup.com.

Nothing here restricts uses the law already allows, such as fair dealing under Kenya's Copyright Act.

Corrections

Found a figure you believe is wrong? Email info@serrarigroup.com with the page URL and the source you would like us to check it against. Changes to how figures are produced are recorded in the change log below. See also our editorial standards.

Change log

1. Version 2.8 · 20 October 2026

   • Published which money market funds the KES and USD series cover, listed from the same data as the rate tables, with the date the rates were recorded.
   • Stated that rates are recorded daily from the figures fund managers publish, that every rate in a table carries the same record date, and that a fund with no figure for that date is left out rather than shown with an older one.

2. Version 2.7 · 29 September 2026

   • Corrected the savings account section: the table shows the minimum balance where published, not a monthly fee. Version 2.6 said it showed both.
   • The CBK benchmark rate on the savings page is no longer counted as a bank product in the citation.

3. Version 2.6 · 29 September 2026

   • Published how the Treasury bond, unit trust and savings account figures are produced. All three pages carried real data with no method behind it.
   • Stated that bond withholding tax follows the original term of the issue — 10% over ten years, 15% at ten years or under — and that infrastructure bonds are exempt.
   • Stated plainly that savings rates are checked rather than fed, so the date shown is the date of the check and can be several weeks old.
   • Added a citation line and dataset description for Kenya bonds, unit trusts and savings accounts. The bond average covers government bonds only, not the listed corporate bonds; the unit trust average covers fixed income funds only.
   • Stated that unit trust yields are shown before withholding tax, and that no after-tax unit trust figure is published.

4. Version 2.5 · 28 September 2026

   • Named the three people responsible for every published dataset and what each of them does: Montel Kamau (Financial Analyst), Rosemary Wambui (Data Analyst) and David Kabera (Data Engineer). The page previously justified every figure on the site while attributing the work to nobody.
   • Added a Definitions section publishing the ten house terms our data pages use, each linked to the section that explains how the figure is produced.
   • Stated that none of the people named is remunerated by a provider listed on the site.

5. Version 2.4 · 24 September 2026

   • Named and defined the Serrari Fixed Deposit Index: the simple average of each bank’s best published rate, divided by the number of banks that publish one, calculated separately for KES and USD.
   • Stated that a tiered, ranged or negotiable rate enters the index at the top of its range, and that the index then reads “up to”.
   • Added a citation line and dataset description for fixed deposit rates on /ke/fd and /ke/fd-usd.

6. Version 2.3 · 21 September 2026

   • Defined the Treasury bill figures Serrari publishes: the latest CBK auction rate per tenor with its auction date, and the monthly average auction rate per tenor for the past twelve months.
   • Added a citation line and dataset description for Kenya Treasury bill auction rates on /ke/tbills.

7. Version 2.2 · 21 September 2026

   • Published the terms for using Serrari data: free to quote with attribution and to embed official widgets; bulk copying, redistribution and resale need written permission.

8. Version 2.1 · 21 September 2026

   • Published the Serrari Kenya MMF Leaders Index definition adopted on 21 September 2026: five members, rebalanced on the 1st of each month, qualifying on three months of top-five rankings.
   • Disclosed that until that definition is implemented, the Leaders Index figure shown is the average of the five highest yields in the latest data.
   • Corrected /ke/mmf, which described the current figure as a three-month average rebalanced monthly.

9. Version 2.0 · 18 September 2026

   • Rewrote every section to describe the data pipeline as it actually runs.
   • Removed the claim that Serrari compounds MMF yields with (1 + r/365)^365 − 1. Serrari publishes the annual yield each manager announces, unchanged.
   • Removed the claim that tied funds are ordered by AUM. Funds with the same yield share a rank.
   • Replaced "licensed redistributor APIs" with the real sources of the JSE, NGX and EGX figures, and noted that the JSE level is the Top 40.
   • Added sections for fixed deposits, the MMF Average Index definition, the published history range and how to cite Serrari data.
   • Started this change log. Earlier versions had none.

10. Version 1.0 · 7 May 2026

    • First published version.