Montana Title 46. Criminal Procedure § 46-18-403. Credit for incarceration prior to sentencing

(i) credit must be given only when the custody to be credited is attributable to proceedings related to the same conduct for which the defendant has been convicted;

(ii) an offender is not entitled to credit against multiple sentences for a single period of custody unless the sentences are imposed concurrently;

(iii) an offender is not entitled to credit in a new criminal matter if the offender is currently serving a custodial sentence on a prior offense;

(iv) incarceration directly related to a probation or parole hold only reduces the sentence that the person was serving while on probation or parole;  and

(v) incarceration includes time spent in a correctional institution as defined in 45-2-101 and a secure residential treatment facility if residence is required by court order.