Reinvestment Risk in Mortgage Investing: The Cost of Money Coming Back Too Soon

Most investors read the rate on a mortgage investment as a description of the year ahead. It describes the loan, not the year. Reinvestment risk in mortgage investing is what fills the gap: private mortgages are short, borrowers repay early, and maturing loans are often not renewed. Each time capital comes back it has to be lent again, and the rate, timing and quality of the next loan are all unknown when the first one is made.

This guide is for investors evaluating a private mortgage, a mortgage fund or a mortgage investment corporation (MIC). It is general education, not investment, tax or legal advice.

What is reinvestment risk in mortgage investing?

Reinvestment risk is the chance that money returned to a lender cannot be put back to work at the same rate, or cannot be put back to work straight away. In mortgage investing it arises whenever a loan is repaid, whether at maturity, early, or because the borrower has refinanced elsewhere, and the lender has to find the next loan.

It has two parts. The first is rate: if market rates or private-lending spreads have fallen, the next loan pays less. The second is time: between repayment and the next advance, capital sits in cash earning little or nothing. Bond investors face the same risk; mortgage investors face it more often because the loans are shorter. The mortgage investment glossary defines related terms such as maturity, renewal and discharge.

Why short-term mortgage investments in Canada face it more often

A short-term mortgage investment in Canada turns over many times during an investor’s holding period. A five-year bond returns its principal once; a portfolio of 12-month mortgages returns its principal roughly every year, and a portfolio of shorter loans more often. Lendmax Capital MIC, for example, lends on terms of 3 to 12 months with staggered maturities.

Three features drive the turnover:

• Term length. Private residential mortgages are usually written for short terms because they bridge a borrower to a sale, to a refinance with a bank, or to a recovery in credit. Bridge mortgage investments are the extreme case, with terms measured in months by design.
• Early repayment. Many private mortgages are open, or open after a short closed period, sometimes with a prepayment bonus of a set number of months’ interest. A borrower whose credit improves will often refinance with a lower-cost lender as soon as it can: the exit the lender underwrote for, and the moment its income on that loan stops.
• Non-renewal. At maturity a borrower may repay, refinance elsewhere, sell the property or ask to renew. A renewal keeps capital deployed; a repayment sends it back.

Mortgage investment term length therefore matters twice: it sets how long capital is exposed to one borrower and property, and how often the lender must go back to market.

What happens if the borrower does not renew?

If the borrower does not renew and repays in full at maturity, the mortgage is discharged and the principal returns to the lender with interest to the payout date. Nothing is lost, but income on that capital stops until it is lent again, which is reinvestment risk in its plainest form.

If the borrower does not renew and cannot repay, the problem is no longer reinvestment. It is a maturity default: the lender negotiates an extension, charges default interest where the contract allows, or enforces its security. That path carries a risk of loss of principal, not just lost income. Terms, renewals, early repayment and discharge walks through each exit and what it costs the lender.

How reinvestment risk shows up inside a MIC

In a MIC or mortgage fund, repayments land in the fund rather than in an investor’s own account, so shareholders do not see individual payouts. The risk shows up as cash drag: the share of the fund’s capital that is uninvested at any moment while loans are repaid and new ones are underwritten.

The arithmetic is simple. If a fund’s loans earn an assumed 10% gross but an average of 10% of its capital is held in cash earning nothing, the portfolio earns 9% gross (90% × 10%) before expenses. A fund that keeps cash very low has to find suitable loans quickly, which raises a different question: whether the pace of deployment is pressuring underwriting standards. A fund holding more cash may be choosing caution, or may be struggling to find borrowers it is willing to lend to. The audited financial statements and management’s commentary in the offering memorandum usually show which.

Some cash is necessary. A MIC needs liquidity to meet redemptions, which are usually subject to notice periods and to the board’s right to defer or suspend them; there is no secondary market for most private MIC shares. Liquidity and redemption covers that side of the balance.

Worked example (illustrative)

A direct investor lends $100,000 as a first mortgage on a detached house in London, Ontario, at an assumed 10% annual rate, interest-only, for a 12-month term. A mortgage administrator (in Ontario, a business licensed by FSRA to service loans for others) charges an assumed 0.5% a year on the balance it services. The investor expects:

• Interest: $100,000 × 10% = $10,000
• Administration fee: $100,000 × 0.5% = $500
• Net before tax: $9,500

The borrower refinances with a bank after six months and pays a prepayment bonus of one month’s interest. The capital sits uninvested for two months, then goes into a new mortgage at an assumed 8.5% for the remaining four months.

• Months 1–6: $100,000 × 10% × 6/12 = $5,000.00
• Prepayment bonus: $100,000 × 10% ÷ 12 = $833.33
• Months 7–8: $0
• Months 9–12: $100,000 × 8.5% × 4/12 = $2,833.33
• Interest received: $8,666.67
• Administration fee for the 10 months deployed: $100,000 × 0.5% × 10/12 = $416.67
• Net before tax: $8,250.00

Mortgage interest is fully taxable as income. At an assumed 40% marginal rate, expected after-tax income was $9,500 × 60% = $5,700 and actual after-tax income was $8,250 × 60% = $4,950. Reinvestment cost the investor $750 after tax, about 13% of the income expected. No principal was lost in this example; credit risk on each loan is a separate question. Tax treatment is described as at October 2026; marginal rates vary by province and income, so confirm your own position with a Canadian tax professional.

Short terms cut both ways

Short terms are not simply a cost. The same turnover that creates reinvestment risk lets a lender reprice upward when rates rise, reassess the borrower and property at each maturity, and step away from a market it no longer likes. Long terms do the reverse: they lock in a rate, for better or worse, and lock in the exposure. Interest rate risk for mortgage investors is the mirror image of the risk described here.

Basis of comparison: the same borrower, property and loan-to-value, with only the term changed.

Reinvestment risk also affects how a quoted yield is read. Where mortgage investment returns come from separates interest, lender fees and losses; turnover adds a fourth line, the income given up between loans. A higher target return comes with higher risk, and mortgage investments are not guaranteed. Returns are targets, not promises, and principal can be lost.

What to check in the documents

Reinvestment risk is visible in documents most investors already receive:

• Term mix and maturity profile of the portfolio: offering memorandum (OM) and the notes to the audited financial statements, where a maturity breakdown is disclosed.
• Cash as a share of total assets at each year-end: audited balance sheet, compared across several years.
• Prepayment terms (open, closed, bonus): the mortgage commitment and the standard charge terms registered on title, for a direct loan.
• Renewal policy and renewal fees: the OM for a fund; the commitment for a direct loan.
• How uninvested cash affects distributions: the OM’s distribution policy and the statement of comprehensive income.
• Redemption terms, notice periods and deferral rights: the OM and the articles of the MIC.

For market-wide mortgage data, CMHC publishes its Residential Mortgage Industry Report.

Common mistakes

• Annualising one loan’s rate as the year’s return. A 10% loan held for six months, followed by idle cash, does not produce 10% for the year.
• Treating a prepayment bonus as a windfall. It is usually small compared with the months of income lost, as the example shows.
• Stretching for longer terms only to avoid reinvestment. A longer term trades reinvestment risk for a longer exposure to one borrower and property.
• Reading a fund’s cash balance as automatically good or bad. High cash can mean caution or a shortage of borrowers; low cash can mean discipline or pressure. The trend and management’s explanation matter.
• Confusing non-renewal with non-payment. A borrower who repays and leaves creates reinvestment risk; a borrower who cannot repay creates credit risk.

What this means for a mortgage investor

Reinvestment risk is the income cost of capital coming back before the investor is ready for it, and in private mortgage investing it is structural rather than occasional. It is managed through term mix, staggered maturities and steady origination, not eliminated. When comparing opportunities, investors can weigh it alongside the seven axes on which mortgage investments vary: the borrower, the property, the loan-to-value, the security position, the term, the jurisdiction and the investment structure.